lora_pipeline.py 257 KB
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# Copyright 2024 The HuggingFace Team. All rights reserved.
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#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
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import os
from typing import Callable, Dict, List, Optional, Union

import torch
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from huggingface_hub.utils import validate_hf_hub_args
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from ..utils import (
    USE_PEFT_BACKEND,
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    deprecate,
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    get_submodule_by_name,
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    is_bitsandbytes_available,
    is_gguf_available,
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    is_peft_available,
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    is_peft_version,
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    is_torch_version,
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    is_transformers_available,
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    is_transformers_version,
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    logging,
)
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from .lora_base import (  # noqa
    LORA_WEIGHT_NAME,
    LORA_WEIGHT_NAME_SAFE,
    LoraBaseMixin,
    _fetch_state_dict,
    _load_lora_into_text_encoder,
)
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from .lora_conversion_utils import (
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    _convert_bfl_flux_control_lora_to_diffusers,
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    _convert_hunyuan_video_lora_to_diffusers,
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    _convert_kohya_flux_lora_to_diffusers,
    _convert_non_diffusers_lora_to_diffusers,
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    _convert_non_diffusers_lumina2_lora_to_diffusers,
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    _convert_non_diffusers_wan_lora_to_diffusers,
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    _convert_xlabs_flux_lora_to_diffusers,
    _maybe_map_sgm_blocks_to_diffusers,
)
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_LOW_CPU_MEM_USAGE_DEFAULT_LORA = False
if is_torch_version(">=", "1.9.0"):
    if (
        is_peft_available()
        and is_peft_version(">=", "0.13.1")
        and is_transformers_available()
        and is_transformers_version(">", "4.45.2")
    ):
        _LOW_CPU_MEM_USAGE_DEFAULT_LORA = True


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logger = logging.get_logger(__name__)

TEXT_ENCODER_NAME = "text_encoder"
UNET_NAME = "unet"
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TRANSFORMER_NAME = "transformer"
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_MODULE_NAME_TO_ATTRIBUTE_MAP_FLUX = {"x_embedder": "in_channels"}

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def _maybe_dequantize_weight_for_expanded_lora(model, module):
    if is_bitsandbytes_available():
        from ..quantizers.bitsandbytes import dequantize_bnb_weight

    if is_gguf_available():
        from ..quantizers.gguf.utils import dequantize_gguf_tensor

    is_bnb_4bit_quantized = module.weight.__class__.__name__ == "Params4bit"
    is_gguf_quantized = module.weight.__class__.__name__ == "GGUFParameter"

    if is_bnb_4bit_quantized and not is_bitsandbytes_available():
        raise ValueError(
            "The checkpoint seems to have been quantized with `bitsandbytes` (4bits). Install `bitsandbytes` to load quantized checkpoints."
        )
    if is_gguf_quantized and not is_gguf_available():
        raise ValueError(
            "The checkpoint seems to have been quantized with `gguf`. Install `gguf` to load quantized checkpoints."
        )

    weight_on_cpu = False
    if not module.weight.is_cuda:
        weight_on_cpu = True

    if is_bnb_4bit_quantized:
        module_weight = dequantize_bnb_weight(
            module.weight.cuda() if weight_on_cpu else module.weight,
            state=module.weight.quant_state,
            dtype=model.dtype,
        ).data
    elif is_gguf_quantized:
        module_weight = dequantize_gguf_tensor(
            module.weight.cuda() if weight_on_cpu else module.weight,
        )
        module_weight = module_weight.to(model.dtype)
    else:
        module_weight = module.weight.data

    if weight_on_cpu:
        module_weight = module_weight.cpu()

    return module_weight


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class StableDiffusionLoraLoaderMixin(LoraBaseMixin):
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    r"""
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    Load LoRA layers into Stable Diffusion [`UNet2DConditionModel`] and
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    [`CLIPTextModel`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel).
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    """
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    _lora_loadable_modules = ["unet", "text_encoder"]
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    unet_name = UNET_NAME
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    text_encoder_name = TEXT_ENCODER_NAME
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    def load_lora_weights(
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        self,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        adapter_name=None,
        hotswap: bool = False,
        **kwargs,
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    ):
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        """Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.unet` and
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        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

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        See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is
        loaded.
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        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_unet`] for more details on how the state dict is
        loaded into `self.unet`.
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        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder`] for more details on how the state
        dict is loaded into `self.text_encoder`.
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        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
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                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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            adapter_name (`str`, *optional*):
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                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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        """
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        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

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        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict, network_alphas = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

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        is_correct_format = all("lora" in key for key in state_dict.keys())
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        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_unet(
            state_dict,
            network_alphas=network_alphas,
            unet=getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet,
            adapter_name=adapter_name,
            _pipeline=self,
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            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=network_alphas,
            text_encoder=getattr(self, self.text_encoder_name)
            if not hasattr(self, "text_encoder")
            else self.text_encoder,
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
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            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
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    @validate_hf_hub_args
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    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
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        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>
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        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
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                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
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                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.
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            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
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            token (`str` or *bool*, *optional*):
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                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.
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            weight_name (`str`, *optional*, defaults to None):
                Name of the serialized state dict file.
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        """
        # Load the main state dict first which has the LoRA layers for either of
        # UNet and text encoder or both.
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        cache_dir = kwargs.pop("cache_dir", None)
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        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
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        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
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        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        unet_config = kwargs.pop("unet_config", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

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        state_dict = _fetch_state_dict(
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            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )
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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}
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        network_alphas = None
        # TODO: replace it with a method from `state_dict_utils`
        if all(
            (
                k.startswith("lora_te_")
                or k.startswith("lora_unet_")
                or k.startswith("lora_te1_")
                or k.startswith("lora_te2_")
            )
            for k in state_dict.keys()
        ):
            # Map SDXL blocks correctly.
            if unet_config is not None:
                # use unet config to remap block numbers
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                state_dict = _maybe_map_sgm_blocks_to_diffusers(state_dict, unet_config)
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            state_dict, network_alphas = _convert_non_diffusers_lora_to_diffusers(state_dict)
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        return state_dict, network_alphas

    @classmethod
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    def load_lora_into_unet(
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        cls,
        state_dict,
        network_alphas,
        unet,
        adapter_name=None,
        _pipeline=None,
        low_cpu_mem_usage=False,
        hotswap: bool = False,
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    ):
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        """
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        This will load the LoRA layers specified in `state_dict` into `unet`.
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        Parameters:
            state_dict (`dict`):
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                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
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            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            unet (`UNet2DConditionModel`):
                The UNet model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
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                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # If the serialization format is new (introduced in https://github.com/huggingface/diffusers/pull/2918),
        # then the `state_dict` keys should have `cls.unet_name` and/or `cls.text_encoder_name` as
        # their prefixes.
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        logger.info(f"Loading {cls.unet_name}.")
        unet.load_lora_adapter(
            state_dict,
            prefix=cls.unet_name,
            network_alphas=network_alphas,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        adapter_name=None,
        _pipeline=None,
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        low_cpu_mem_usage=False,
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        hotswap: bool = False,
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `text_encoder`

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        _load_lora_into_text_encoder(
            state_dict=state_dict,
            network_alphas=network_alphas,
            lora_scale=lora_scale,
            text_encoder=text_encoder,
            prefix=prefix,
            text_encoder_name=cls.text_encoder_name,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        unet_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_lora_layers: Dict[str, torch.nn.Module] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
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        Save the LoRA parameters corresponding to the UNet and text encoder.
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        Arguments:
            save_directory (`str` or `os.PathLike`):
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                Directory to save LoRA parameters to. Will be created if it doesn't exist.
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            unet_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `unet`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
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                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
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                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
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                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
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        """
        state_dict = {}

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        if not (unet_lora_layers or text_encoder_lora_layers):
            raise ValueError("You must pass at least one of `unet_lora_layers` and `text_encoder_lora_layers`.")
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        if unet_lora_layers:
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            state_dict.update(cls.pack_weights(unet_lora_layers, cls.unet_name))
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        if text_encoder_lora_layers:
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            state_dict.update(cls.pack_weights(text_encoder_lora_layers, cls.text_encoder_name))
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        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    def fuse_lora(
        self,
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        components: List[str] = ["unet", "text_encoder"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
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        **kwargs,
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    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
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            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
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            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
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        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )
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    def unfuse_lora(self, components: List[str] = ["unet", "text_encoder"], **kwargs):
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        r"""
        Reverses the effect of
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        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).
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        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
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            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
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            unfuse_unet (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
            unfuse_text_encoder (`bool`, defaults to `True`):
                Whether to unfuse the text encoder LoRA parameters. If the text encoder wasn't monkey-patched with the
                LoRA parameters then it won't have any effect.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class StableDiffusionXLLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into Stable Diffusion XL [`UNet2DConditionModel`],
    [`CLIPTextModel`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel), and
    [`CLIPTextModelWithProjection`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModelWithProjection).
    """
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    _lora_loadable_modules = ["unet", "text_encoder", "text_encoder_2"]
    unet_name = UNET_NAME
    text_encoder_name = TEXT_ENCODER_NAME
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    def load_lora_weights(
        self,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        adapter_name: Optional[str] = None,
        **kwargs,
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.unet` and
        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

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        See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is
        loaded.
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        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_unet`] for more details on how the state dict is
        loaded into `self.unet`.
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        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder`] for more details on how the state
        dict is loaded into `self.text_encoder`.
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        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
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                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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            adapter_name (`str`, *optional*):
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                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            kwargs (`dict`, *optional*):
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                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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        """
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        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # We could have accessed the unet config from `lora_state_dict()` too. We pass
        # it here explicitly to be able to tell that it's coming from an SDXL
        # pipeline.

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        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

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        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict, network_alphas = self.lora_state_dict(
            pretrained_model_name_or_path_or_dict,
            unet_config=self.unet.config,
            **kwargs,
        )
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        is_correct_format = all("lora" in key for key in state_dict.keys())
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        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_unet(
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            state_dict,
            network_alphas=network_alphas,
            unet=self.unet,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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        )
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        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=network_alphas,
            text_encoder=self.text_encoder,
            prefix=self.text_encoder_name,
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )
        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=network_alphas,
            text_encoder=self.text_encoder_2,
            prefix=f"{self.text_encoder_name}_2",
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )
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    @classmethod
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    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.lora_state_dict
    def lora_state_dict(
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        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
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        r"""
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        Return state dict for lora weights and the network alphas.
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        <Tip warning={true}>
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        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.
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            weight_name (`str`, *optional*, defaults to None):
                Name of the serialized state dict file.
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        """
        # Load the main state dict first which has the LoRA layers for either of
        # UNet and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
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        unet_config = kwargs.pop("unet_config", None)
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        use_safetensors = kwargs.pop("use_safetensors", None)
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        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

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        state_dict = _fetch_state_dict(
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            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )
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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}
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        network_alphas = None
        # TODO: replace it with a method from `state_dict_utils`
        if all(
            (
                k.startswith("lora_te_")
                or k.startswith("lora_unet_")
                or k.startswith("lora_te1_")
                or k.startswith("lora_te2_")
            )
            for k in state_dict.keys()
        ):
            # Map SDXL blocks correctly.
            if unet_config is not None:
                # use unet config to remap block numbers
                state_dict = _maybe_map_sgm_blocks_to_diffusers(state_dict, unet_config)
            state_dict, network_alphas = _convert_non_diffusers_lora_to_diffusers(state_dict)

        return state_dict, network_alphas

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.load_lora_into_unet
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    def load_lora_into_unet(
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        cls,
        state_dict,
        network_alphas,
        unet,
        adapter_name=None,
        _pipeline=None,
        low_cpu_mem_usage=False,
        hotswap: bool = False,
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    ):
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        """
        This will load the LoRA layers specified in `state_dict` into `unet`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            network_alphas (`Dict[str, float]`):
                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
            unet (`UNet2DConditionModel`):
                The UNet model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # If the serialization format is new (introduced in https://github.com/huggingface/diffusers/pull/2918),
        # then the `state_dict` keys should have `cls.unet_name` and/or `cls.text_encoder_name` as
        # their prefixes.
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        logger.info(f"Loading {cls.unet_name}.")
        unet.load_lora_adapter(
            state_dict,
            prefix=cls.unet_name,
            network_alphas=network_alphas,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        adapter_name=None,
        _pipeline=None,
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `text_encoder`

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        _load_lora_into_text_encoder(
            state_dict=state_dict,
            network_alphas=network_alphas,
            lora_scale=lora_scale,
            text_encoder=text_encoder,
            prefix=prefix,
            text_encoder_name=cls.text_encoder_name,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        unet_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_2_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            unet_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `unet`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            text_encoder_2_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder_2`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not (unet_lora_layers or text_encoder_lora_layers or text_encoder_2_lora_layers):
            raise ValueError(
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                "You must pass at least one of `unet_lora_layers`, `text_encoder_lora_layers`, `text_encoder_2_lora_layers`."
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            )

        if unet_lora_layers:
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            state_dict.update(cls.pack_weights(unet_lora_layers, cls.unet_name))
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        if text_encoder_lora_layers:
            state_dict.update(cls.pack_weights(text_encoder_lora_layers, "text_encoder"))

        if text_encoder_2_lora_layers:
            state_dict.update(cls.pack_weights(text_encoder_2_lora_layers, "text_encoder_2"))

        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    def fuse_lora(
        self,
        components: List[str] = ["unet", "text_encoder", "text_encoder_2"],
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

    def unfuse_lora(self, components: List[str] = ["unet", "text_encoder", "text_encoder_2"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_unet (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
            unfuse_text_encoder (`bool`, defaults to `True`):
                Whether to unfuse the text encoder LoRA parameters. If the text encoder wasn't monkey-patched with the
                LoRA parameters then it won't have any effect.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class SD3LoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`SD3Transformer2DModel`],
    [`CLIPTextModel`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel), and
    [`CLIPTextModelWithProjection`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModelWithProjection).

    Specific to [`StableDiffusion3Pipeline`].
    """

    _lora_loadable_modules = ["transformer", "text_encoder", "text_encoder_2"]
    transformer_name = TRANSFORMER_NAME
    text_encoder_name = TEXT_ENCODER_NAME

    @classmethod
    @validate_hf_hub_args
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

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        state_dict = _fetch_state_dict(
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            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

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        return state_dict

    def load_lora_weights(
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        self,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        adapter_name=None,
        hotswap: bool = False,
        **kwargs,
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    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.unet` and
        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

        See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is
        loaded.

        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

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        is_correct_format = all("lora" in key for key in state_dict.keys())
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        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

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        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=None,
            text_encoder=self.text_encoder,
            prefix=self.text_encoder_name,
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=None,
            text_encoder=self.text_encoder_2,
            prefix=f"{self.text_encoder_name}_2",
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
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    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
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        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`SD3Transformer2DModel`):
                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        adapter_name=None,
        _pipeline=None,
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        low_cpu_mem_usage=False,
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        hotswap: bool = False,
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `text_encoder`

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        _load_lora_into_text_encoder(
            state_dict=state_dict,
            network_alphas=network_alphas,
            lora_scale=lora_scale,
            text_encoder=text_encoder,
            prefix=prefix,
            text_encoder_name=cls.text_encoder_name,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
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    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionXLLoraLoaderMixin.save_lora_weights with unet->transformer
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    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
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        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
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        text_encoder_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_2_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            text_encoder_2_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder_2`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not (transformer_lora_layers or text_encoder_lora_layers or text_encoder_2_lora_layers):
            raise ValueError(
                "You must pass at least one of `transformer_lora_layers`, `text_encoder_lora_layers`, `text_encoder_2_lora_layers`."
            )

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        if text_encoder_lora_layers:
            state_dict.update(cls.pack_weights(text_encoder_lora_layers, "text_encoder"))

        if text_encoder_2_lora_layers:
            state_dict.update(cls.pack_weights(text_encoder_2_lora_layers, "text_encoder_2"))

        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionXLLoraLoaderMixin.fuse_lora with unet->transformer
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    def fuse_lora(
        self,
        components: List[str] = ["transformer", "text_encoder", "text_encoder_2"],
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionXLLoraLoaderMixin.unfuse_lora with unet->transformer
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    def unfuse_lora(self, components: List[str] = ["transformer", "text_encoder", "text_encoder_2"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>
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        This is an experimental API.
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        </Tip>
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        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
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            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
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            unfuse_text_encoder (`bool`, defaults to `True`):
                Whether to unfuse the text encoder LoRA parameters. If the text encoder wasn't monkey-patched with the
                LoRA parameters then it won't have any effect.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class FluxLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`FluxTransformer2DModel`],
    [`CLIPTextModel`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel).

    Specific to [`StableDiffusion3Pipeline`].
    """

    _lora_loadable_modules = ["transformer", "text_encoder"]
    transformer_name = TRANSFORMER_NAME
    text_encoder_name = TEXT_ENCODER_NAME
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    _control_lora_supported_norm_keys = ["norm_q", "norm_k", "norm_added_q", "norm_added_k"]
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    @classmethod
    @validate_hf_hub_args
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
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        return_alphas: bool = False,
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        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

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        state_dict = _fetch_state_dict(
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            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )
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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}
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        # TODO (sayakpaul): to a follow-up to clean and try to unify the conditions.
        is_kohya = any(".lora_down.weight" in k for k in state_dict)
        if is_kohya:
            state_dict = _convert_kohya_flux_lora_to_diffusers(state_dict)
            # Kohya already takes care of scaling the LoRA parameters with alpha.
            return (state_dict, None) if return_alphas else state_dict

        is_xlabs = any("processor" in k for k in state_dict)
        if is_xlabs:
            state_dict = _convert_xlabs_flux_lora_to_diffusers(state_dict)
            # xlabs doesn't use `alpha`.
            return (state_dict, None) if return_alphas else state_dict

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        is_bfl_control = any("query_norm.scale" in k for k in state_dict)
        if is_bfl_control:
            state_dict = _convert_bfl_flux_control_lora_to_diffusers(state_dict)
            return (state_dict, None) if return_alphas else state_dict

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        # For state dicts like
        # https://huggingface.co/TheLastBen/Jon_Snow_Flux_LoRA
        keys = list(state_dict.keys())
        network_alphas = {}
        for k in keys:
            if "alpha" in k:
                alpha_value = state_dict.get(k)
                if (torch.is_tensor(alpha_value) and torch.is_floating_point(alpha_value)) or isinstance(
                    alpha_value, float
                ):
                    network_alphas[k] = state_dict.pop(k)
                else:
                    raise ValueError(
                        f"The alpha key ({k}) seems to be incorrect. If you think this error is unexpected, please open as issue."
                    )

        if return_alphas:
            return state_dict, network_alphas
        else:
            return state_dict
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    def load_lora_weights(
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        self,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        adapter_name=None,
        hotswap: bool = False,
        **kwargs,
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    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

        See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is
        loaded.

        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                `Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter. If the new
                adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need to call an
                additional method before loading the adapter:
                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```
                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
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        state_dict, network_alphas = self.lora_state_dict(
            pretrained_model_name_or_path_or_dict, return_alphas=True, **kwargs
        )
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        has_lora_keys = any("lora" in key for key in state_dict.keys())

        # Flux Control LoRAs also have norm keys
        has_norm_keys = any(
            norm_key in key for key in state_dict.keys() for norm_key in self._control_lora_supported_norm_keys
        )

        if not (has_lora_keys or has_norm_keys):
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            raise ValueError("Invalid LoRA checkpoint.")

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        transformer_lora_state_dict = {
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            k: state_dict.get(k)
            for k in list(state_dict.keys())
            if k.startswith(f"{self.transformer_name}.") and "lora" in k
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        }
        transformer_norm_state_dict = {
            k: state_dict.pop(k)
            for k in list(state_dict.keys())
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            if k.startswith(f"{self.transformer_name}.")
            and any(norm_key in k for norm_key in self._control_lora_supported_norm_keys)
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        }

        transformer = getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer
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        has_param_with_expanded_shape = False
        if len(transformer_lora_state_dict) > 0:
            has_param_with_expanded_shape = self._maybe_expand_transformer_param_shape_or_error_(
                transformer, transformer_lora_state_dict, transformer_norm_state_dict
            )
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        if has_param_with_expanded_shape:
            logger.info(
                "The LoRA weights contain parameters that have different shapes that expected by the transformer. "
                "As a result, the state_dict of the transformer has been expanded to match the LoRA parameter shapes. "
                "To get a comprehensive list of parameter names that were modified, enable debug logging."
            )
        if len(transformer_lora_state_dict) > 0:
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            transformer_lora_state_dict = self._maybe_expand_lora_state_dict(
                transformer=transformer, lora_state_dict=transformer_lora_state_dict
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            )
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            for k in transformer_lora_state_dict:
                state_dict.update({k: transformer_lora_state_dict[k]})

        self.load_lora_into_transformer(
            state_dict,
            network_alphas=network_alphas,
            transformer=transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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        if len(transformer_norm_state_dict) > 0:
            transformer._transformer_norm_layers = self._load_norm_into_transformer(
                transformer_norm_state_dict,
                transformer=transformer,
                discard_original_layers=False,
            )

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        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=network_alphas,
            text_encoder=self.text_encoder,
            prefix=self.text_encoder_name,
            lora_scale=self.lora_scale,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
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    def load_lora_into_transformer(
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        cls,
        state_dict,
        network_alphas,
        transformer,
        adapter_name=None,
        _pipeline=None,
        low_cpu_mem_usage=False,
        hotswap: bool = False,
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    ):
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        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
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            network_alphas (`Dict[str, float]`):
                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            transformer (`FluxTransformer2DModel`):
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                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # Load the layers corresponding to transformer.
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        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=network_alphas,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    def _load_norm_into_transformer(
        cls,
        state_dict,
        transformer,
        prefix=None,
        discard_original_layers=False,
    ) -> Dict[str, torch.Tensor]:
        # Remove prefix if present
        prefix = prefix or cls.transformer_name
        for key in list(state_dict.keys()):
            if key.split(".")[0] == prefix:
                state_dict[key[len(f"{prefix}.") :]] = state_dict.pop(key)

        # Find invalid keys
        transformer_state_dict = transformer.state_dict()
        transformer_keys = set(transformer_state_dict.keys())
        state_dict_keys = set(state_dict.keys())
        extra_keys = list(state_dict_keys - transformer_keys)

        if extra_keys:
            logger.warning(
                f"Unsupported keys found in state dict when trying to load normalization layers into the transformer. The following keys will be ignored:\n{extra_keys}."
            )

        for key in extra_keys:
            state_dict.pop(key)

        # Save the layers that are going to be overwritten so that unload_lora_weights can work as expected
        overwritten_layers_state_dict = {}
        if not discard_original_layers:
            for key in state_dict.keys():
                overwritten_layers_state_dict[key] = transformer_state_dict[key].clone()

        logger.info(
            "The provided state dict contains normalization layers in addition to LoRA layers. The normalization layers will directly update the state_dict of the transformer "
            'as opposed to the LoRA layers that will co-exist separately until the "fuse_lora()" method is called. That is to say, the normalization layers will always be directly '
            "fused into the transformer and can only be unfused if `discard_original_layers=True` is passed. This might also have implications when dealing with multiple LoRAs. "
            "If you notice something unexpected, please open an issue: https://github.com/huggingface/diffusers/issues."
        )

        # We can't load with strict=True because the current state_dict does not contain all the transformer keys
        incompatible_keys = transformer.load_state_dict(state_dict, strict=False)
        unexpected_keys = getattr(incompatible_keys, "unexpected_keys", None)

        # We shouldn't expect to see the supported norm keys here being present in the unexpected keys.
        if unexpected_keys:
            if any(norm_key in k for k in unexpected_keys for norm_key in cls._control_lora_supported_norm_keys):
                raise ValueError(
                    f"Found {unexpected_keys} as unexpected keys while trying to load norm layers into the transformer."
                )

        return overwritten_layers_state_dict

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    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        adapter_name=None,
        _pipeline=None,
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        low_cpu_mem_usage=False,
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        hotswap: bool = False,
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `text_encoder`

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        _load_lora_into_text_encoder(
            state_dict=state_dict,
            network_alphas=network_alphas,
            lora_scale=lora_scale,
            text_encoder=text_encoder,
            prefix=prefix,
            text_encoder_name=cls.text_encoder_name,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.save_lora_weights with unet->transformer
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_lora_layers: Dict[str, torch.nn.Module] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not (transformer_lora_layers or text_encoder_lora_layers):
            raise ValueError("You must pass at least one of `transformer_lora_layers` and `text_encoder_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        if text_encoder_lora_layers:
            state_dict.update(cls.pack_weights(text_encoder_lora_layers, cls.text_encoder_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
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        transformer = getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer
        if (
            hasattr(transformer, "_transformer_norm_layers")
            and isinstance(transformer._transformer_norm_layers, dict)
            and len(transformer._transformer_norm_layers.keys()) > 0
        ):
            logger.info(
                "The provided state dict contains normalization layers in addition to LoRA layers. The normalization layers will be directly updated the state_dict of the transformer "
                "as opposed to the LoRA layers that will co-exist separately until the 'fuse_lora()' method is called. That is to say, the normalization layers will always be directly "
                "fused into the transformer and can only be unfused if `discard_original_layers=True` is passed."
            )

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        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

    def unfuse_lora(self, components: List[str] = ["transformer", "text_encoder"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
        """
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        transformer = getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer
        if hasattr(transformer, "_transformer_norm_layers") and transformer._transformer_norm_layers:
            transformer.load_state_dict(transformer._transformer_norm_layers, strict=False)

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        super().unfuse_lora(components=components, **kwargs)
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    # We override this here account for `_transformer_norm_layers` and `_overwritten_params`.
    def unload_lora_weights(self, reset_to_overwritten_params=False):
        """
        Unloads the LoRA parameters.

        Args:
            reset_to_overwritten_params (`bool`, defaults to `False`): Whether to reset the LoRA-loaded modules
                to their original params. Refer to the [Flux
                documentation](https://huggingface.co/docs/diffusers/main/en/api/pipelines/flux) to learn more.

        Examples:

        ```python
        >>> # Assuming `pipeline` is already loaded with the LoRA parameters.
        >>> pipeline.unload_lora_weights()
        >>> ...
        ```
        """
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        super().unload_lora_weights()

        transformer = getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer
        if hasattr(transformer, "_transformer_norm_layers") and transformer._transformer_norm_layers:
            transformer.load_state_dict(transformer._transformer_norm_layers, strict=False)
            transformer._transformer_norm_layers = None

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        if reset_to_overwritten_params and getattr(transformer, "_overwritten_params", None) is not None:
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            overwritten_params = transformer._overwritten_params
            module_names = set()

            for param_name in overwritten_params:
                if param_name.endswith(".weight"):
                    module_names.add(param_name.replace(".weight", ""))

            for name, module in transformer.named_modules():
                if isinstance(module, torch.nn.Linear) and name in module_names:
                    module_weight = module.weight.data
                    module_bias = module.bias.data if module.bias is not None else None
                    bias = module_bias is not None

                    parent_module_name, _, current_module_name = name.rpartition(".")
                    parent_module = transformer.get_submodule(parent_module_name)

                    current_param_weight = overwritten_params[f"{name}.weight"]
                    in_features, out_features = current_param_weight.shape[1], current_param_weight.shape[0]
                    with torch.device("meta"):
                        original_module = torch.nn.Linear(
                            in_features,
                            out_features,
                            bias=bias,
                            dtype=module_weight.dtype,
                        )

                    tmp_state_dict = {"weight": current_param_weight}
                    if module_bias is not None:
                        tmp_state_dict.update({"bias": overwritten_params[f"{name}.bias"]})
                    original_module.load_state_dict(tmp_state_dict, assign=True, strict=True)
                    setattr(parent_module, current_module_name, original_module)

                    del tmp_state_dict

                    if current_module_name in _MODULE_NAME_TO_ATTRIBUTE_MAP_FLUX:
                        attribute_name = _MODULE_NAME_TO_ATTRIBUTE_MAP_FLUX[current_module_name]
                        new_value = int(current_param_weight.shape[1])
                        old_value = getattr(transformer.config, attribute_name)
                        setattr(transformer.config, attribute_name, new_value)
                        logger.info(
                            f"Set the {attribute_name} attribute of the model to {new_value} from {old_value}."
                        )

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    @classmethod
    def _maybe_expand_transformer_param_shape_or_error_(
        cls,
        transformer: torch.nn.Module,
        lora_state_dict=None,
        norm_state_dict=None,
        prefix=None,
    ) -> bool:
        """
        Control LoRA expands the shape of the input layer from (3072, 64) to (3072, 128). This method handles that and
        generalizes things a bit so that any parameter that needs expansion receives appropriate treatement.
        """
        state_dict = {}
        if lora_state_dict is not None:
            state_dict.update(lora_state_dict)
        if norm_state_dict is not None:
            state_dict.update(norm_state_dict)

        # Remove prefix if present
        prefix = prefix or cls.transformer_name
        for key in list(state_dict.keys()):
            if key.split(".")[0] == prefix:
                state_dict[key[len(f"{prefix}.") :]] = state_dict.pop(key)

        # Expand transformer parameter shapes if they don't match lora
        has_param_with_shape_update = False
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        overwritten_params = {}

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        is_peft_loaded = getattr(transformer, "peft_config", None) is not None
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        is_quantized = hasattr(transformer, "hf_quantizer")
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        for name, module in transformer.named_modules():
            if isinstance(module, torch.nn.Linear):
                module_weight = module.weight.data
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                module_bias = module.bias.data if module.bias is not None else None
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                bias = module_bias is not None

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                lora_base_name = name.replace(".base_layer", "") if is_peft_loaded else name
                lora_A_weight_name = f"{lora_base_name}.lora_A.weight"
                lora_B_weight_name = f"{lora_base_name}.lora_B.weight"
                if lora_A_weight_name not in state_dict:
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                    continue

                in_features = state_dict[lora_A_weight_name].shape[1]
                out_features = state_dict[lora_B_weight_name].shape[0]

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                # Model maybe loaded with different quantization schemes which may flatten the params.
                # `bitsandbytes`, for example, flatten the weights when using 4bit. 8bit bnb models
                # preserve weight shape.
                module_weight_shape = cls._calculate_module_shape(model=transformer, base_module=module)

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                # This means there's no need for an expansion in the params, so we simply skip.
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                if tuple(module_weight_shape) == (out_features, in_features):
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                    continue

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                module_out_features, module_in_features = module_weight_shape
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                debug_message = ""
                if in_features > module_in_features:
                    debug_message += (
                        f'Expanding the nn.Linear input/output features for module="{name}" because the provided LoRA '
                        f"checkpoint contains higher number of features than expected. The number of input_features will be "
                        f"expanded from {module_in_features} to {in_features}"
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                    )
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                if out_features > module_out_features:
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                    debug_message += (
                        ", and the number of output features will be "
                        f"expanded from {module_out_features} to {out_features}."
                    )
                else:
                    debug_message += "."
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                if debug_message:
                    logger.debug(debug_message)

                if out_features > module_out_features or in_features > module_in_features:
                    has_param_with_shape_update = True
                    parent_module_name, _, current_module_name = name.rpartition(".")
                    parent_module = transformer.get_submodule(parent_module_name)

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                    if is_quantized:
                        module_weight = _maybe_dequantize_weight_for_expanded_lora(transformer, module)

                    # TODO: consider if this layer needs to be a quantized layer as well if `is_quantized` is True.
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                    with torch.device("meta"):
                        expanded_module = torch.nn.Linear(
                            in_features, out_features, bias=bias, dtype=module_weight.dtype
                        )
                    # Only weights are expanded and biases are not. This is because only the input dimensions
                    # are changed while the output dimensions remain the same. The shape of the weight tensor
                    # is (out_features, in_features), while the shape of bias tensor is (out_features,), which
                    # explains the reason why only weights are expanded.
                    new_weight = torch.zeros_like(
                        expanded_module.weight.data, device=module_weight.device, dtype=module_weight.dtype
                    )
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                    slices = tuple(slice(0, dim) for dim in module_weight_shape)
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                    new_weight[slices] = module_weight
                    tmp_state_dict = {"weight": new_weight}
                    if module_bias is not None:
                        tmp_state_dict["bias"] = module_bias
                    expanded_module.load_state_dict(tmp_state_dict, strict=True, assign=True)

                    setattr(parent_module, current_module_name, expanded_module)

                    del tmp_state_dict

                    if current_module_name in _MODULE_NAME_TO_ATTRIBUTE_MAP_FLUX:
                        attribute_name = _MODULE_NAME_TO_ATTRIBUTE_MAP_FLUX[current_module_name]
                        new_value = int(expanded_module.weight.data.shape[1])
                        old_value = getattr(transformer.config, attribute_name)
                        setattr(transformer.config, attribute_name, new_value)
                        logger.info(
                            f"Set the {attribute_name} attribute of the model to {new_value} from {old_value}."
                        )
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                    # For `unload_lora_weights()`.
                    # TODO: this could lead to more memory overhead if the number of overwritten params
                    # are large. Should be revisited later and tackled through a `discard_original_layers` arg.
                    overwritten_params[f"{current_module_name}.weight"] = module_weight
                    if module_bias is not None:
                        overwritten_params[f"{current_module_name}.bias"] = module_bias

        if len(overwritten_params) > 0:
            transformer._overwritten_params = overwritten_params

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        return has_param_with_shape_update
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    @classmethod
    def _maybe_expand_lora_state_dict(cls, transformer, lora_state_dict):
        expanded_module_names = set()
        transformer_state_dict = transformer.state_dict()
        prefix = f"{cls.transformer_name}."

        lora_module_names = [
            key[: -len(".lora_A.weight")] for key in lora_state_dict if key.endswith(".lora_A.weight")
        ]
        lora_module_names = [name[len(prefix) :] for name in lora_module_names if name.startswith(prefix)]
        lora_module_names = sorted(set(lora_module_names))
        transformer_module_names = sorted({name for name, _ in transformer.named_modules()})
        unexpected_modules = set(lora_module_names) - set(transformer_module_names)
        if unexpected_modules:
            logger.debug(f"Found unexpected modules: {unexpected_modules}. These will be ignored.")

        is_peft_loaded = getattr(transformer, "peft_config", None) is not None
        for k in lora_module_names:
            if k in unexpected_modules:
                continue

            base_param_name = (
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                f"{k.replace(prefix, '')}.base_layer.weight"
                if is_peft_loaded and f"{k.replace(prefix, '')}.base_layer.weight" in transformer_state_dict
                else f"{k.replace(prefix, '')}.weight"
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            )
            base_weight_param = transformer_state_dict[base_param_name]
            lora_A_param = lora_state_dict[f"{prefix}{k}.lora_A.weight"]

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            # TODO (sayakpaul): Handle the cases when we actually need to expand when using quantization.
            base_module_shape = cls._calculate_module_shape(model=transformer, base_weight_param_name=base_param_name)

            if base_module_shape[1] > lora_A_param.shape[1]:
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                shape = (lora_A_param.shape[0], base_weight_param.shape[1])
                expanded_state_dict_weight = torch.zeros(shape, device=base_weight_param.device)
                expanded_state_dict_weight[:, : lora_A_param.shape[1]].copy_(lora_A_param)
                lora_state_dict[f"{prefix}{k}.lora_A.weight"] = expanded_state_dict_weight
                expanded_module_names.add(k)
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            elif base_module_shape[1] < lora_A_param.shape[1]:
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                raise NotImplementedError(
                    f"This LoRA param ({k}.lora_A.weight) has an incompatible shape {lora_A_param.shape}. Please open an issue to file for a feature request - https://github.com/huggingface/diffusers/issues/new."
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                )

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        if expanded_module_names:
            logger.info(
                f"The following LoRA modules were zero padded to match the state dict of {cls.transformer_name}: {expanded_module_names}. Please open an issue if you think this was unexpected - https://github.com/huggingface/diffusers/issues/new."
            )
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        return lora_state_dict
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    @staticmethod
    def _calculate_module_shape(
        model: "torch.nn.Module",
        base_module: "torch.nn.Linear" = None,
        base_weight_param_name: str = None,
    ) -> "torch.Size":
        def _get_weight_shape(weight: torch.Tensor):
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            if weight.__class__.__name__ == "Params4bit":
                return weight.quant_state.shape
            elif weight.__class__.__name__ == "GGUFParameter":
                return weight.quant_shape
            else:
                return weight.shape
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        if base_module is not None:
            return _get_weight_shape(base_module.weight)
        elif base_weight_param_name is not None:
            if not base_weight_param_name.endswith(".weight"):
                raise ValueError(
                    f"Invalid `base_weight_param_name` passed as it does not end with '.weight' {base_weight_param_name=}."
                )
            module_path = base_weight_param_name.rsplit(".weight", 1)[0]
            submodule = get_submodule_by_name(model, module_path)
            return _get_weight_shape(submodule.weight)

        raise ValueError("Either `base_module` or `base_weight_param_name` must be provided.")

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# The reason why we subclass from `StableDiffusionLoraLoaderMixin` here is because Amused initially
# relied on `StableDiffusionLoraLoaderMixin` for its LoRA support.
class AmusedLoraLoaderMixin(StableDiffusionLoraLoaderMixin):
    _lora_loadable_modules = ["transformer", "text_encoder"]
    transformer_name = TRANSFORMER_NAME
    text_encoder_name = TEXT_ENCODER_NAME
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    @classmethod
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    # Copied from diffusers.loaders.lora_pipeline.FluxLoraLoaderMixin.load_lora_into_transformer with FluxTransformer2DModel->UVit2DModel
    def load_lora_into_transformer(
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        cls,
        state_dict,
        network_alphas,
        transformer,
        adapter_name=None,
        _pipeline=None,
        low_cpu_mem_usage=False,
        hotswap: bool = False,
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    ):
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        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
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            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            transformer (`UVit2DModel`):
                The Transformer model to load the LoRA layers into.
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            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        if low_cpu_mem_usage and not is_peft_version(">=", "0.13.1"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )
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        # Load the layers corresponding to transformer.
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        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=network_alphas,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.load_lora_into_text_encoder
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        adapter_name=None,
        _pipeline=None,
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        low_cpu_mem_usage=False,
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        hotswap: bool = False,
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `text_encoder`

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
            network_alphas (`Dict[str, float]`):
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                The value of the network alpha used for stable learning and preventing underflow. This value has the
                same meaning as the `--network_alpha` option in the kohya-ss trainer script. Refer to [this
                link](https://github.com/darkstorm2150/sd-scripts/blob/main/docs/train_network_README-en.md#execute-learning).
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            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        _load_lora_into_text_encoder(
            state_dict=state_dict,
            network_alphas=network_alphas,
            lora_scale=lora_scale,
            text_encoder=text_encoder,
            prefix=prefix,
            text_encoder_name=cls.text_encoder_name,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
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        text_encoder_lora_layers: Dict[str, torch.nn.Module] = None,
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        transformer_lora_layers: Dict[str, torch.nn.Module] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
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            unet_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `unet`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
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            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

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        if not (transformer_lora_layers or text_encoder_lora_layers):
            raise ValueError("You must pass at least one of `transformer_lora_layers` or `text_encoder_lora_layers`.")
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        if transformer_lora_layers:
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            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))
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        if text_encoder_lora_layers:
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            state_dict.update(cls.pack_weights(text_encoder_lora_layers, cls.text_encoder_name))
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        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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class CogVideoXLoraLoaderMixin(LoraBaseMixin):
    r"""
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    Load LoRA layers into [`CogVideoXTransformer3DModel`]. Specific to [`CogVideoXPipeline`].
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    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.lora_state_dict
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

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        state_dict = _fetch_state_dict(
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            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

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        return state_dict

    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
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        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

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        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

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        is_correct_format = all("lora" in key for key in state_dict.keys())
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        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
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            low_cpu_mem_usage=low_cpu_mem_usage,
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        )

    @classmethod
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    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->CogVideoXTransformer3DModel
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    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
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        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
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            transformer (`CogVideoXTransformer3DModel`):
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                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
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            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
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        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

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        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )
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    @classmethod
    # Adapted from diffusers.loaders.lora_pipeline.StableDiffusionLoraLoaderMixin.save_lora_weights without support for text encoder
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
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        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
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        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class Mochi1LoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`MochiTransformer3DModel`]. Specific to [`MochiPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.lora_state_dict
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
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    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->MochiTransformer3DModel
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    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
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            transformer (`MochiTransformer3DModel`):
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                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
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                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
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    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
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    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
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        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class LTXVideoLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`LTXVideoTransformer3DModel`]. Specific to [`LTXPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.lora_state_dict
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->LTXVideoTransformer3DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`LTXVideoTransformer3DModel`):
                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
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                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
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    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
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    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
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        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class SanaLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`SanaTransformer2DModel`]. Specific to [`SanaPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.lora_state_dict
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->SanaTransformer2DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`SanaTransformer2DModel`):
                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
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                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
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    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
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    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
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        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class HunyuanVideoLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`HunyuanVideoTransformer3DModel`]. Specific to [`HunyuanVideoPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

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        We support loading original format HunyuanVideo LoRA checkpoints.
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        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

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        is_original_hunyuan_video = any("img_attn_qkv" in k for k in state_dict)
        if is_original_hunyuan_video:
            state_dict = _convert_hunyuan_video_lora_to_diffusers(state_dict)

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        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->HunyuanVideoTransformer3DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`HunyuanVideoTransformer3DModel`):
                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
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                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
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        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
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    def fuse_lora(
        self,
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        components: List[str] = ["transformer"],
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        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

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    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
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    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
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        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class Lumina2LoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`Lumina2Transformer2DModel`]. Specific to [`Lumina2Text2ImgPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

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        # conversion.
        non_diffusers = any(k.startswith("diffusion_model.") for k in state_dict)
        if non_diffusers:
            state_dict = _convert_non_diffusers_lumina2_lora_to_diffusers(state_dict)

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        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->Lumina2Transformer2DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`Lumina2Transformer2DModel`):
                The Transformer model to load the LoRA layers into.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    # Copied from diffusers.loaders.lora_pipeline.SanaLoraLoaderMixin.fuse_lora
    def fuse_lora(
        self,
        components: List[str] = ["transformer"],
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

    # Copied from diffusers.loaders.lora_pipeline.SanaLoraLoaderMixin.unfuse_lora
    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class WanLoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`WanTransformer3DModel`]. Specific to [`WanPipeline`] and `[WanImageToVideoPipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )
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        if any(k.startswith("diffusion_model.") for k in state_dict):
            state_dict = _convert_non_diffusers_wan_lora_to_diffusers(state_dict)
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        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

        return state_dict

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    @classmethod
    def _maybe_expand_t2v_lora_for_i2v(
        cls,
        transformer: torch.nn.Module,
        state_dict,
    ):
        if transformer.config.image_dim is None:
            return state_dict

        if any(k.startswith("transformer.blocks.") for k in state_dict):
            num_blocks = len({k.split("blocks.")[1].split(".")[0] for k in state_dict})
            is_i2v_lora = any("add_k_proj" in k for k in state_dict) and any("add_v_proj" in k for k in state_dict)

            if is_i2v_lora:
                return state_dict

            for i in range(num_blocks):
                for o, c in zip(["k_img", "v_img"], ["add_k_proj", "add_v_proj"]):
                    state_dict[f"transformer.blocks.{i}.attn2.{c}.lora_A.weight"] = torch.zeros_like(
                        state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_A.weight"]
                    )
                    state_dict[f"transformer.blocks.{i}.attn2.{c}.lora_B.weight"] = torch.zeros_like(
                        state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_B.weight"]
                    )

        return state_dict

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    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)
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        # convert T2V LoRA to I2V LoRA (when loaded to Wan I2V) by adding zeros for the additional (missing) _img layers
        state_dict = self._maybe_expand_t2v_lora_for_i2v(
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            state_dict=state_dict,
        )
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        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->WanTransformer3DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`WanTransformer3DModel`):
                The Transformer model to load the LoRA layers into.
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            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
    def fuse_lora(
        self,
        components: List[str] = ["transformer"],
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class CogView4LoraLoaderMixin(LoraBaseMixin):
    r"""
    Load LoRA layers into [`WanTransformer3DModel`]. Specific to [`CogView4Pipeline`].
    """

    _lora_loadable_modules = ["transformer"]
    transformer_name = TRANSFORMER_NAME

    @classmethod
    @validate_hf_hub_args
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.lora_state_dict
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.

            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
            token (`str` or *bool*, *optional*):
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.

        """
        # Load the main state dict first which has the LoRA layers for either of
        # transformer and text encoder or both.
        cache_dir = kwargs.pop("cache_dir", None)
        force_download = kwargs.pop("force_download", False)
        proxies = kwargs.pop("proxies", None)
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        state_dict = _fetch_state_dict(
            pretrained_model_name_or_path_or_dict=pretrained_model_name_or_path_or_dict,
            weight_name=weight_name,
            use_safetensors=use_safetensors,
            local_files_only=local_files_only,
            cache_dir=cache_dir,
            force_download=force_download,
            proxies=proxies,
            token=token,
            revision=revision,
            subfolder=subfolder,
            user_agent=user_agent,
            allow_pickle=allow_pickle,
        )

        is_dora_scale_present = any("dora_scale" in k for k in state_dict)
        if is_dora_scale_present:
            warn_msg = "It seems like you are using a DoRA checkpoint that is not compatible in Diffusers at the moment. So, we are going to filter out the keys associated to 'dora_scale` from the state dict. If you think this is a mistake please open an issue https://github.com/huggingface/diffusers/issues/new."
            logger.warning(warn_msg)
            state_dict = {k: v for k, v in state_dict.items() if "dora_scale" not in k}

        return state_dict

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.load_lora_weights
    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.transformer` and
        `self.text_encoder`. All kwargs are forwarded to `self.lora_state_dict`. See
        [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.
        See [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_into_transformer`] for more details on how the state
        dict is loaded into `self.transformer`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
            kwargs (`dict`, *optional*):
                See [`~loaders.StableDiffusionLoraLoaderMixin.lora_state_dict`].
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT_LORA)
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

        is_correct_format = all("lora" in key for key in state_dict.keys())
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_transformer(
            state_dict,
            transformer=getattr(self, self.transformer_name) if not hasattr(self, "transformer") else self.transformer,
            adapter_name=adapter_name,
            _pipeline=self,
            low_cpu_mem_usage=low_cpu_mem_usage,
        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.SD3LoraLoaderMixin.load_lora_into_transformer with SD3Transformer2DModel->CogView4Transformer2DModel
    def load_lora_into_transformer(
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        cls, state_dict, transformer, adapter_name=None, _pipeline=None, low_cpu_mem_usage=False, hotswap: bool = False
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    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            transformer (`CogView4Transformer2DModel`):
                The Transformer model to load the LoRA layers into.
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            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            low_cpu_mem_usage (`bool`, *optional*):
                Speed up model loading by only loading the pretrained LoRA weights and not initializing the random
                weights.
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            hotswap : (`bool`, *optional*)
                Defaults to `False`. Whether to substitute an existing (LoRA) adapter with the newly loaded adapter
                in-place. This means that, instead of loading an additional adapter, this will take the existing
                adapter weights and replace them with the weights of the new adapter. This can be faster and more
                memory efficient. However, the main advantage of hotswapping is that when the model is compiled with
                torch.compile, loading the new adapter does not require recompilation of the model. When using
                hotswapping, the passed `adapter_name` should be the name of an already loaded adapter.

                If the new adapter and the old adapter have different ranks and/or LoRA alphas (i.e. scaling), you need
                to call an additional method before loading the adapter:

                ```py
                pipeline = ...  # load diffusers pipeline
                max_rank = ...  # the highest rank among all LoRAs that you want to load
                # call *before* compiling and loading the LoRA adapter
                pipeline.enable_lora_hotswap(target_rank=max_rank)
                pipeline.load_lora_weights(file_name)
                # optionally compile the model now
                ```

                Note that hotswapping adapters of the text encoder is not yet supported. There are some further
                limitations to this technique, which are documented here:
                https://huggingface.co/docs/peft/main/en/package_reference/hotswap
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        """
        if low_cpu_mem_usage and is_peft_version("<", "0.13.0"):
            raise ValueError(
                "`low_cpu_mem_usage=True` is not compatible with this `peft` version. Please update it with `pip install -U peft`."
            )

        # Load the layers corresponding to transformer.
        logger.info(f"Loading {cls.transformer_name}.")
        transformer.load_lora_adapter(
            state_dict,
            network_alphas=None,
            adapter_name=adapter_name,
            _pipeline=_pipeline,
            low_cpu_mem_usage=low_cpu_mem_usage,
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            hotswap=hotswap,
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        )

    @classmethod
    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.save_lora_weights
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        transformer_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            transformer_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `transformer`.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        if not transformer_lora_layers:
            raise ValueError("You must pass `transformer_lora_layers`.")

        if transformer_lora_layers:
            state_dict.update(cls.pack_weights(transformer_lora_layers, cls.transformer_name))

        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.fuse_lora
    def fuse_lora(
        self,
        components: List[str] = ["transformer"],
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
        adapter_names: Optional[List[str]] = None,
        **kwargs,
    ):
        r"""
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components: (`List[str]`): List of LoRA-injectable components to fuse the LoRAs into.
            lora_scale (`float`, defaults to 1.0):
                Controls how much to influence the outputs with the LoRA parameters.
            safe_fusing (`bool`, defaults to `False`):
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
        """
        super().fuse_lora(
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            components=components,
            lora_scale=lora_scale,
            safe_fusing=safe_fusing,
            adapter_names=adapter_names,
            **kwargs,
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        )

    # Copied from diffusers.loaders.lora_pipeline.CogVideoXLoraLoaderMixin.unfuse_lora
    def unfuse_lora(self, components: List[str] = ["transformer"], **kwargs):
        r"""
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraBaseMixin.fuse_lora).

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            components (`List[str]`): List of LoRA-injectable components to unfuse LoRA from.
            unfuse_transformer (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
        """
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        super().unfuse_lora(components=components, **kwargs)
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class LoraLoaderMixin(StableDiffusionLoraLoaderMixin):
    def __init__(self, *args, **kwargs):
        deprecation_message = "LoraLoaderMixin is deprecated and this will be removed in a future version. Please use `StableDiffusionLoraLoaderMixin`, instead."
        deprecate("LoraLoaderMixin", "1.0.0", deprecation_message)
        super().__init__(*args, **kwargs)