Merge branch 'master' into pr/1383

examples/distillation/scripts/extract.py

+# coding=utf-8
+# Copyright 2019-present, the HuggingFace Inc. team.
+#
+# 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.
+"""
+Preprocessing script before training the distilled model.
+Specific to RoBERTa -> DistilRoBERTa and GPT2 -> DistilGPT2.
+"""
+from transformers import BertForMaskedLM, RobertaForMaskedLM, GPT2LMHeadModel
+import torch
+import argparse
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description="Extraction some layers of the full RobertaForMaskedLM or GPT2LMHeadModel for Transfer Learned Distillation")
+    parser.add_argument("--model_type", default="roberta", choices=["roberta", "gpt2"])
+    parser.add_argument("--model_name", default='roberta-large', type=str)
+    parser.add_argument("--dump_checkpoint", default='serialization_dir/tf_roberta_048131723.pth', type=str)
+    parser.add_argument("--vocab_transform", action='store_true')
+    args = parser.parse_args()
+
+
+    if args.model_type == 'roberta':
+        model = RobertaForMaskedLM.from_pretrained(args.model_name)
+        prefix = 'roberta'
+    elif args.model_type == 'gpt2':
+        model = GPT2LMHeadModel.from_pretrained(args.model_name)
+        prefix = 'transformer'
+
+    state_dict = model.state_dict()
+    compressed_sd = {}
+
+    ### Embeddings ###
+    if args.model_type == 'gpt2':
+        for param_name in ['wte.weight', 'wpe.weight']:
+            compressed_sd[f'{prefix}.{param_name}'] = state_dict[f'{prefix}.{param_name}']
+    else:
+        for w in ['word_embeddings', 'position_embeddings', 'token_type_embeddings']:
+            param_name = f'{prefix}.embeddings.{w}.weight'
+            compressed_sd[param_name] = state_dict[param_name]
+        for w in ['weight', 'bias']:
+            param_name = f'{prefix}.embeddings.LayerNorm.{w}'
+            compressed_sd[param_name] = state_dict[param_name]
+
+    ### Transformer Blocks ###
+    std_idx = 0
+    for teacher_idx in [0, 2, 4, 7, 9, 11]:
+        if args.model_type == 'gpt2':
+            for layer in ['ln_1', 'attn.c_attn', 'attn.c_proj', 'ln_2', 'mlp.c_fc', 'mlp.c_proj']:
+                for w in ['weight', 'bias']:
+                    compressed_sd[f'{prefix}.h.{std_idx}.{layer}.{w}'] = \
+                        state_dict[f'{prefix}.h.{teacher_idx}.{layer}.{w}']
+            compressed_sd[f'{prefix}.h.{std_idx}.attn.bias'] = state_dict[f'{prefix}.h.{teacher_idx}.attn.bias']
+        else:
+            for layer in ['attention.self.query', 'attention.self.key', 'attention.self.value',
+                        'attention.output.dense', 'attention.output.LayerNorm',
+                        'intermediate.dense', 'output.dense', 'output.LayerNorm']:
+                for w in ['weight', 'bias']:
+                    compressed_sd[f'{prefix}.encoder.layer.{std_idx}.{layer}.{w}'] = \
+                        state_dict[f'{prefix}.encoder.layer.{teacher_idx}.{layer}.{w}']
+        std_idx += 1
+
+    ### Language Modeling Head ###s
+    if args.model_type == 'roberta':
+        for layer in ['lm_head.decoder.weight', 'lm_head.bias']:
+            compressed_sd[f'{layer}'] = state_dict[f'{layer}']
+        if args.vocab_transform:
+            for w in ['weight', 'bias']:
+                compressed_sd[f'lm_head.dense.{w}'] = state_dict[f'lm_head.dense.{w}']
+                compressed_sd[f'lm_head.layer_norm.{w}'] = state_dict[f'lm_head.layer_norm.{w}']
+    elif args.model_type == 'gpt2':
+        for w in ['weight', 'bias']:
+            compressed_sd[f'{prefix}.ln_f.{w}'] = state_dict[f'{prefix}.ln_f.{w}']
+        compressed_sd[f'lm_head.weight'] = state_dict[f'lm_head.weight']
+
+    print(f'N layers selected for distillation: {std_idx}')
+    print(f'Number of params transfered for distillation: {len(compressed_sd.keys())}')
+
+    print(f'Save transfered checkpoint to {args.dump_checkpoint}.')
+    torch.save(compressed_sd, args.dump_checkpoint)

examples/distillation/scripts/extract_for_distil.py → examples/distillation/scripts/extract_distilbert.py

@@ -14,6 +14,7 @@
 # limitations under the License.
 """
 Preprocessing script before training DistilBERT.
+Specific to BERT -> DistilBERT.
 """
 from transformers import BertForMaskedLM, RobertaForMaskedLM
 import torch
@@ -21,7 +22,7 @@ import argparse
 
 if __name__ == '__main__':
     parser = argparse.ArgumentParser(description="Extraction some layers of the full BertForMaskedLM or RObertaForMaskedLM for Transfer Learned Distillation")
-    parser.add_argument("--model_type", default="bert", choices=["bert", "roberta"])
+    parser.add_argument("--model_type", default="bert", choices=["bert"])
     parser.add_argument("--model_name", default='bert-base-uncased', type=str)
     parser.add_argument("--dump_checkpoint", default='serialization_dir/tf_bert-base-uncased_0247911.pth', type=str)
     parser.add_argument("--vocab_transform", action='store_true')
@@ -31,9 +32,8 @@ if __name__ == '__main__':
     if args.model_type == 'bert':
         model = BertForMaskedLM.from_pretrained(args.model_name)
         prefix = 'bert'
-    elif args.model_type == 'roberta':
-        model = RobertaForMaskedLM.from_pretrained(args.model_name)
-        prefix = 'roberta'
+    else:
+        raise ValueError(f'args.model_type should be "bert".')
 
     state_dict = model.state_dict()
     compressed_sd = {}
@@ -68,20 +68,12 @@ if __name__ == '__main__':
                 state_dict[f'{prefix}.encoder.layer.{teacher_idx}.output.LayerNorm.{w}']
         std_idx += 1
 
-    if args.model_type == 'bert':
-        compressed_sd[f'vocab_projector.weight'] = state_dict[f'cls.predictions.decoder.weight']
-        compressed_sd[f'vocab_projector.bias'] = state_dict[f'cls.predictions.bias']
-        if args.vocab_transform:
-            for w in ['weight', 'bias']:
-                compressed_sd[f'vocab_transform.{w}'] = state_dict[f'cls.predictions.transform.dense.{w}']
-                compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'cls.predictions.transform.LayerNorm.{w}']
-    elif args.model_type == 'roberta':
-        compressed_sd[f'vocab_projector.weight'] = state_dict[f'lm_head.decoder.weight']
-        compressed_sd[f'vocab_projector.bias'] = state_dict[f'lm_head.bias']
-        if args.vocab_transform:
-            for w in ['weight', 'bias']:
-                compressed_sd[f'vocab_transform.{w}'] = state_dict[f'lm_head.dense.{w}']
-                compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'lm_head.layer_norm.{w}']
+    compressed_sd[f'vocab_projector.weight'] = state_dict[f'cls.predictions.decoder.weight']
+    compressed_sd[f'vocab_projector.bias'] = state_dict[f'cls.predictions.bias']
+    if args.vocab_transform:
+        for w in ['weight', 'bias']:
+            compressed_sd[f'vocab_transform.{w}'] = state_dict[f'cls.predictions.transform.dense.{w}']
+            compressed_sd[f'vocab_layer_norm.{w}'] = state_dict[f'cls.predictions.transform.LayerNorm.{w}']
 
     print(f'N layers selected for distillation: {std_idx}')
     print(f'Number of params transfered for distillation: {len(compressed_sd.keys())}')

examples/distillation/scripts/token_counts.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 """
-Preprocessing script before training DistilBERT.
+Preprocessing script before training the distilled model.
 """
 from collections import Counter
 import argparse

examples/distillation/train.py

@@ -13,7 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 """
-Training DistilBERT.
+Training the distilled model.
+Supported architectures include: BERT -> DistilBERT, RoBERTa -> DistilRoBERTa, GPT2 -> DistilGPT2.
 """
 import os
 import argparse
@@ -23,68 +24,96 @@ import shutil
 import numpy as np
 import torch
 
-from transformers import BertTokenizer, BertForMaskedLM, RobertaTokenizer, RobertaForMaskedLM
-from transformers import DistilBertForMaskedLM, DistilBertConfig
+from transformers import BertConfig, BertForMaskedLM, BertTokenizer
+from transformers import RobertaConfig, RobertaForMaskedLM, RobertaTokenizer
+from transformers import DistilBertConfig, DistilBertForMaskedLM, DistilBertTokenizer
+from transformers import GPT2Config, GPT2LMHeadModel, GPT2Tokenizer
 
 from distiller import Distiller
 from utils import git_log, logger, init_gpu_params, set_seed
-from dataset import Dataset
+from lm_seqs_dataset import LmSeqsDataset
+
+
+MODEL_CLASSES = {
+    'distilbert': (DistilBertConfig, DistilBertForMaskedLM, DistilBertTokenizer),
+    'roberta': (RobertaConfig, RobertaForMaskedLM, RobertaTokenizer),
+    'bert': (BertConfig, BertForMaskedLM, BertTokenizer),
+    'gpt2': (GPT2Config, GPT2LMHeadModel, GPT2Tokenizer)
+}
+
+def sanity_checks(args):
+    """
+    A bunch of args sanity checks to perform even starting...
+    """
+    assert (args.mlm and args.alpha_mlm > 0.) or (not args.mlm and args.alpha_mlm == 0.)
+    assert (args.alpha_mlm > 0. and args.alpha_clm == 0.) or (args.alpha_mlm == 0. and args.alpha_clm > 0.)
+    if args.mlm:
+        assert os.path.isfile(args.token_counts)
+        assert (args.student_type in ['roberta', 'distilbert']) and (args.teacher_type in ['roberta', 'bert'])
+    else:
+        assert (args.student_type in ['gpt2']) and (args.teacher_type in ['gpt2'])
+
+    assert args.teacher_type == args.student_type or (args.student_type=='distilbert' and args.teacher_type=='bert')
+    assert os.path.isfile(args.student_config)
+    if args.student_pretrained_weights is not None:
+        assert os.path.isfile(args.student_pretrained_weights)
+
+    if args.freeze_token_type_embds: assert args.student_type in ['roberta']
+
+    assert args.alpha_ce >= 0.
+    assert args.alpha_mlm >= 0.
+    assert args.alpha_clm >= 0.
+    assert args.alpha_mse >= 0.
+    assert args.alpha_cos >= 0.
+    assert args.alpha_ce + args.alpha_mlm + args.alpha_clm + args.alpha_mse + args.alpha_cos > 0.
+
+def freeze_pos_embeddings(student, args):
+    if args.student_type == 'roberta':
+        student.roberta.embeddings.position_embeddings.weight.requires_grad = False
+    elif args.student_type == 'gpt2':
+        student.transformer.wpe.weight.requires_grad = False
 
+def freeze_token_type_embeddings(student, args):
+    if args.student_type == 'roberta':
+        student.roberta.embeddings.token_type_embeddings.weight.requires_grad = False
 
 def main():
     parser = argparse.ArgumentParser(description="Training")
+    parser.add_argument("--force", action='store_true',
+                        help="Overwrite dump_path if it already exists.")
 
     parser.add_argument("--dump_path", type=str, required=True,
                         help="The output directory (log, checkpoints, parameters, etc.)")
     parser.add_argument("--data_file", type=str, required=True,
                         help="The binarized file (tokenized + tokens_to_ids) and grouped by sequence.")
-    parser.add_argument("--token_counts", type=str, required=True,
-                        help="The token counts in the data_file for MLM.")
-    parser.add_argument("--force", action='store_true',
-                        help="Overwrite dump_path if it already exists.")
 
-    parser.add_argument("--vocab_size", default=30522, type=int,
-                        help="The vocabulary size.")
-    parser.add_argument("--max_position_embeddings", default=512, type=int,
-                        help="Maximum sequence length we can model (including [CLS] and [SEP]).")
-    parser.add_argument("--sinusoidal_pos_embds", action='store_false',
-                        help="If true, the position embeddings are simply fixed with sinusoidal embeddings.")
-    parser.add_argument("--n_layers", default=6, type=int,
-                        help="Number of Transformer blocks.")
-    parser.add_argument("--n_heads", default=12, type=int,
-                        help="Number of heads in the self-attention module.")
-    parser.add_argument("--dim", default=768, type=int,
-                        help="Dimension through the network. Must be divisible by n_heads")
-    parser.add_argument("--hidden_dim", default=3072, type=int,
-                        help="Intermediate dimension in the FFN.")
-    parser.add_argument("--dropout", default=0.1, type=float,
-                        help="Dropout.")
-    parser.add_argument("--attention_dropout", default=0.1, type=float,
-                        help="Dropout in self-attention.")
-    parser.add_argument("--activation", default='gelu', type=str,
-                        help="Activation to use in self-attention")
-    parser.add_argument("--tie_weights_", action='store_false',
-                        help="If true, we tie the embeddings matrix with the projection over the vocabulary matrix. Default is true.")
-
-    parser.add_argument("--from_pretrained_weights", default=None, type=str,
+    parser.add_argument("--student_type", type=str, choices=["distilbert", "roberta", "gpt2"], required=True,
+                        help="The student type (DistilBERT, RoBERTa).")
+    parser.add_argument("--student_config", type=str, required=True,
+                        help="Path to the student configuration.")
+    parser.add_argument("--student_pretrained_weights", default=None, type=str,
                         help="Load student initialization checkpoint.")
-    parser.add_argument("--from_pretrained_config", default=None, type=str,
-                        help="Load student initialization architecture config.")
-    parser.add_argument("--teacher_type", default="bert", choices=["bert", "roberta"],
+
+    parser.add_argument("--teacher_type", choices=["bert", "roberta", "gpt2"], required=True,
                         help="Teacher type (BERT, RoBERTa).")
-    parser.add_argument("--teacher_name", default="bert-base-uncased", type=str,
+    parser.add_argument("--teacher_name", type=str, required=True,
                         help="The teacher model.")
 
     parser.add_argument("--temperature", default=2., type=float,
                         help="Temperature for the softmax temperature.")
     parser.add_argument("--alpha_ce", default=0.5, type=float,
                         help="Linear weight for the distillation loss. Must be >=0.")
-    parser.add_argument("--alpha_mlm", default=0.5, type=float,
-                        help="Linear weight for the MLM loss. Must be >=0.")
+    parser.add_argument("--alpha_mlm", default=0.0, type=float,
+                        help="Linear weight for the MLM loss. Must be >=0. Should be used in coonjunction with `mlm` flag.")
+    parser.add_argument("--alpha_clm", default=0.5, type=float,
+                        help="Linear weight for the CLM loss. Must be >=0.")
     parser.add_argument("--alpha_mse", default=0.0, type=float,
                         help="Linear weight of the MSE loss. Must be >=0.")
     parser.add_argument("--alpha_cos", default=0.0, type=float,
                         help="Linear weight of the cosine embedding loss. Must be >=0.")
+
+    parser.add_argument("--mlm", action="store_true",
+                        help="The LM step: MLM or CLM. If `mlm` is True, the MLM is used over CLM.")
     parser.add_argument("--mlm_mask_prop", default=0.15, type=float,
                         help="Proportion of tokens for which we need to make a prediction.")
     parser.add_argument("--word_mask", default=0.8, type=float,
@@ -95,17 +124,20 @@ def main():
                         help="Proportion of tokens to randomly replace.")
     parser.add_argument("--mlm_smoothing", default=0.7, type=float,
                         help="Smoothing parameter to emphasize more rare tokens (see XLM, similar to word2vec).")
+    parser.add_argument("--token_counts", type=str,
+                        help="The token counts in the data_file for MLM.")
+
     parser.add_argument("--restrict_ce_to_mask", action='store_true',
                         help="If true, compute the distilation loss only the [MLM] prediction distribution.")
+    parser.add_argument("--freeze_pos_embs", action="store_true",
+                        help="Freeze positional embeddings during distillation. For student_type in ['roberta', 'gpt2'] only.")
+    parser.add_argument("--freeze_token_type_embds", action="store_true",
+                        help="Freeze token type embeddings during distillation if existent. For student_type in ['roberta'] only.")
 
     parser.add_argument("--n_epoch", type=int, default=3,
                         help="Number of pass on the whole dataset.")
     parser.add_argument("--batch_size", type=int, default=5,
                         help="Batch size (for each process).")
-    parser.add_argument("--tokens_per_batch", type=int, default=-1,
-                        help="If specified, modify the batches so that they have approximately this number of tokens.")
-    parser.add_argument("--shuffle", action='store_false',
-                        help="If true, shuffle the sequence order. Default is true.")
     parser.add_argument("--group_by_size", action='store_false',
                         help="If true, group sequences that have similar length into the same batch. Default is true.")
 
@@ -141,6 +173,7 @@ def main():
     parser.add_argument("--checkpoint_interval", type=int, default=4000,
                         help="Checkpoint interval.")
     args = parser.parse_args()
+    sanity_checks(args)
 
 
     ## ARGS ##
@@ -164,21 +197,19 @@ def main():
         with open(os.path.join(args.dump_path, 'parameters.json'), 'w') as f:
             json.dump(vars(args), f, indent=4)
         git_log(args.dump_path)
-    assert (args.from_pretrained_weights is None and args.from_pretrained_config is None) or \
-           (args.from_pretrained_weights is not None and args.from_pretrained_config is not None)
 
+    student_config_class, student_model_class, _ = MODEL_CLASSES[args.student_type]
+    teacher_config_class, teacher_model_class, teacher_tokenizer_class = MODEL_CLASSES[args.teacher_type]
 
     ### TOKENIZER ###
-    if args.teacher_type == 'bert':
-        tokenizer = BertTokenizer.from_pretrained(args.teacher_name)
-    elif args.teacher_type == 'roberta':
-        tokenizer = RobertaTokenizer.from_pretrained(args.teacher_name)
+    tokenizer = teacher_tokenizer_class.from_pretrained(args.teacher_name)
     special_tok_ids = {}
     for tok_name, tok_symbol in tokenizer.special_tokens_map.items():
         idx = tokenizer.all_special_tokens.index(tok_symbol)
         special_tok_ids[tok_name] = tokenizer.all_special_ids[idx]
     logger.info(f'Special tokens {special_tok_ids}')
     args.special_tok_ids = special_tok_ids
+    args.max_model_input_size = tokenizer.max_model_input_sizes[args.teacher_name]
 
 
     ## DATA LOADER ##
@@ -187,35 +218,34 @@ def main():
         data = pickle.load(fp)
 
 
-    assert os.path.isfile(args.token_counts)
-    logger.info(f'Loading token counts from {args.token_counts} (already pre-computed)')
-    with open(args.token_counts, 'rb') as fp:
-        counts = pickle.load(fp)
-        assert len(counts) == args.vocab_size
-    token_probs = np.maximum(counts, 1) ** -args.mlm_smoothing
-    for idx in special_tok_ids.values():
-        token_probs[idx] = 0.  # do not predict special tokens
-    token_probs = torch.from_numpy(token_probs)
+    if args.mlm:
+        logger.info(f'Loading token counts from {args.token_counts} (already pre-computed)')
+        with open(args.token_counts, 'rb') as fp:
+            counts = pickle.load(fp)
+        
+        token_probs = np.maximum(counts, 1) ** -args.mlm_smoothing
+        for idx in special_tok_ids.values():
+            token_probs[idx] = 0.  # do not predict special tokens
+        token_probs = torch.from_numpy(token_probs)
+    else:
+        token_probs = None
 
 
-    train_dataloader = Dataset(params=args, data=data)
+    train_lm_seq_dataset = LmSeqsDataset(params=args, data=data)
     logger.info(f'Data loader created.')
 
 
     ## STUDENT ##
-    if args.from_pretrained_weights is not None:
-        assert os.path.isfile(args.from_pretrained_weights)
-        assert os.path.isfile(args.from_pretrained_config)
-        logger.info(f'Loading pretrained weights from {args.from_pretrained_weights}')
-        logger.info(f'Loading pretrained config from {args.from_pretrained_config}')
-        stu_architecture_config = DistilBertConfig.from_json_file(args.from_pretrained_config)
-        stu_architecture_config.output_hidden_states = True
-        student = DistilBertForMaskedLM.from_pretrained(args.from_pretrained_weights,
-                                                        config=stu_architecture_config)
+    logger.info(f'Loading student config from {args.student_config}')
+    stu_architecture_config = student_config_class.from_pretrained(args.student_config)
+    stu_architecture_config.output_hidden_states = True
+
+    if args.student_pretrained_weights is not None:
+        logger.info(f'Loading pretrained weights from {args.student_pretrained_weights}')
+        student = student_model_class.from_pretrained(args.student_pretrained_weights,
+                                                      config=stu_architecture_config)
     else:
-        args.vocab_size_or_config_json_file = args.vocab_size
-        stu_architecture_config = DistilBertConfig(**vars(args), output_hidden_states=True)
-        student = DistilBertForMaskedLM(stu_architecture_config)
+        student = student_model_class(stu_architecture_config)
 
 
     if args.n_gpu > 0:
@@ -224,18 +254,31 @@ def main():
 
 
     ## TEACHER ##
-    if args.teacher_type == 'bert':
-        teacher = BertForMaskedLM.from_pretrained(args.teacher_name, output_hidden_states=True)
-    elif args.teacher_type == 'roberta':
-        teacher = RobertaForMaskedLM.from_pretrained(args.teacher_name, output_hidden_states=True)
+    teacher = teacher_model_class.from_pretrained(args.teacher_name, output_hidden_states=True)
     if args.n_gpu > 0:
         teacher.to(f'cuda:{args.local_rank}')
     logger.info(f'Teacher loaded from {args.teacher_name}.')
 
+
+    ## FREEZING ##
+    if args.freeze_pos_embs:
+        freeze_pos_embeddings(student, args)
+    if args.freeze_token_type_embds:
+        freeze_token_type_embeddings(student, args)
+
+
+    ## SANITY CHECKS ##
+    assert student.config.vocab_size == teacher.config.vocab_size
+    assert student.config.hidden_size == teacher.config.hidden_size
+    assert student.config.max_position_embeddings == teacher.config.max_position_embeddings
+    if args.mlm:
+        assert token_probs.size(0) == stu_architecture_config.vocab_size
+
+
     ## DISTILLER ##
     torch.cuda.empty_cache()
     distiller = Distiller(params=args,
-                          dataloader=train_dataloader,
+                          dataset=train_lm_seq_dataset,
                           token_probs=token_probs,
                           student=student,
                           teacher=teacher)

examples/distillation/training_configs/distilbert-base-uncased.json

+{
+	"activation": "gelu",
+	"attention_dropout": 0.1,
+	"dim": 768,
+	"dropout": 0.1,
+	"hidden_dim": 3072,
+	"initializer_range": 0.02,
+	"max_position_embeddings": 512,
+	"n_heads": 12,
+	"n_layers": 6,
+	"sinusoidal_pos_embds": true,
+	"tie_weights_": true,
+	"vocab_size": 30522
+  }
+  
\ No newline at end of file

examples/distillation/training_configs/distilgpt2.json

+{
+	"initializer_range": 0.02,
+	"layer_norm_epsilon": 0.00001,
+	"n_ctx": 1024,
+	"n_embd": 768,
+	"n_head": 12,
+	"n_layer": 6,
+	"n_positions": 1024,
+	"vocab_size": 50257
+}
\ No newline at end of file

examples/run_generation.py

@@ -26,13 +26,15 @@ import torch
 import torch.nn.functional as F
 import numpy as np
 
-from transformers import GPT2Config, OpenAIGPTConfig, XLNetConfig, TransfoXLConfig, CTRLConfig
+from transformers import GPT2Config, OpenAIGPTConfig, XLNetConfig, TransfoXLConfig, XLMConfig, CTRLConfig
 
 from transformers import GPT2LMHeadModel, GPT2Tokenizer
 from transformers import OpenAIGPTLMHeadModel, OpenAIGPTTokenizer
 from transformers import XLNetLMHeadModel, XLNetTokenizer
 from transformers import TransfoXLLMHeadModel, TransfoXLTokenizer
 from transformers import CTRLLMHeadModel, CTRLTokenizer
+from transformers import XLMWithLMHeadModel, XLMTokenizer
+
 
 logging.basicConfig(format = '%(asctime)s - %(levelname)s - %(name)s -   %(message)s',
                     datefmt = '%m/%d/%Y %H:%M:%S',
@@ -41,7 +43,7 @@ logger = logging.getLogger(__name__)
 
 MAX_LENGTH = int(10000)  # Hardcoded max length to avoid infinite loop
 
-ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) for conf in (GPT2Config, OpenAIGPTConfig, XLNetConfig, TransfoXLConfig, CTRLConfig)), ())
+ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) for conf in (GPT2Config, OpenAIGPTConfig, XLNetConfig, TransfoXLConfig, XLMConfig, CTRLConfig)), ())
 
 MODEL_CLASSES = {
     'gpt2': (GPT2LMHeadModel, GPT2Tokenizer),
@@ -49,6 +51,7 @@ MODEL_CLASSES = {
     'openai-gpt': (OpenAIGPTLMHeadModel, OpenAIGPTTokenizer),
     'xlnet': (XLNetLMHeadModel, XLNetTokenizer),
     'transfo-xl': (TransfoXLLMHeadModel, TransfoXLTokenizer),
+    'xlm': (XLMWithLMHeadModel, XLMTokenizer),
 }
 
 # Padding text to help Transformer-XL and XLNet with short prompts as proposed by Aman Rusia
@@ -104,7 +107,7 @@ def top_k_top_p_filtering(logits, top_k=0, top_p=0.0, filter_value=-float('Inf')
     return logits
 
 
-def sample_sequence(model, length, context, num_samples=1, temperature=1, top_k=0, top_p=0.0, repetition_penalty=1.0, is_xlnet=False, device='cpu'):
+def sample_sequence(model, length, context, num_samples=1, temperature=1, top_k=0, top_p=0.0, repetition_penalty=1.0, is_xlnet=False, xlm_lang=None, device='cpu'):
     context = torch.tensor(context, dtype=torch.long, device=device)
     context = context.unsqueeze(0).repeat(num_samples, 1)
     generated = context
@@ -122,6 +125,9 @@ def sample_sequence(model, length, context, num_samples=1, temperature=1, top_k=
                 target_mapping[0, 0, -1] = 1.0  # predict last token
                 inputs = {'input_ids': input_ids, 'perm_mask': perm_mask, 'target_mapping': target_mapping}
 
+            if xlm_lang is not None:
+                inputs["langs"] = torch.tensor([xlm_lang] * inputs["input_ids"].shape[1], device=device).view(1, -1)
+
             outputs = model(**inputs)  # Note: we could also use 'past' with GPT-2/Transfo-XL/XLNet (cached hidden-states)
             next_token_logits = outputs[0][0, -1, :] / (temperature if temperature > 0 else 1.)
 
@@ -146,6 +152,7 @@ def main():
                         help="Path to pre-trained model or shortcut name selected in the list: " + ", ".join(ALL_MODELS))
     parser.add_argument("--prompt", type=str, default="")
     parser.add_argument("--padding_text", type=str, default="")
+    parser.add_argument("--xlm_lang", type=str, default="", help="Optional language when used with the XLM model.")
     parser.add_argument("--length", type=int, default=20)
     parser.add_argument("--temperature", type=float, default=1.0,
                         help="temperature of 0 implies greedy sampling")
@@ -157,6 +164,8 @@ def main():
                         help="Avoid using CUDA when available")
     parser.add_argument('--seed', type=int, default=42,
                         help="random seed for initialization")
+    parser.add_argument('--stop_token', type=str, default=None,
+                        help="Token at which text generation is stopped")
     args = parser.parse_args()
     if args.model_type in ["ctrl"]:
         if args.temperature > 0.7 : 
@@ -183,6 +192,18 @@ def main():
 
     print(args)
     while True:
+        xlm_lang = None
+        # XLM Language usage detailed in the issues #1414
+        if args.model_type in ["xlm"] and hasattr(tokenizer, 'lang2id') and hasattr(model.config, 'use_lang_emb') \
+                and model.config.use_lang_emb:
+            if args.xlm_lang:
+                language = args.xlm_lang
+            else:
+                language = None
+                while language not in tokenizer.lang2id.keys():
+                    language = input("Using XLM. Select language in " + str(list(tokenizer.lang2id.keys())) + " >>> ")
+            xlm_lang = tokenizer.lang2id[language]
+
         raw_text = args.prompt if args.prompt else input("Model prompt >>> ")
         if args.model_type in ["transfo-xl", "xlnet"]:
             # Models with memory likes to have a long prompt for short inputs.
@@ -196,11 +217,15 @@ def main():
             top_k=args.top_k,
             top_p=args.top_p,
             repetition_penalty=args.repetition_penalty,
-            device=args.device,
             is_xlnet=bool(args.model_type == "xlnet"),
+            xlm_lang=xlm_lang,
+            device=args.device,
         )
         out = out[0, len(context_tokens):].tolist()
-        text = tokenizer.decode(out, clean_up_tokenization_spaces=True)
+
+        text = tokenizer.decode(out, clean_up_tokenization_spaces=True, skip_special_tokens=True)
+        text = text[: text.find(args.stop_token) if args.stop_token else None]
+
         print(text)
         if args.prompt:
             break

examples/run_glue.py

@@ -53,7 +53,8 @@ from transformers import glue_convert_examples_to_features as convert_examples_t
 
 logger = logging.getLogger(__name__)
 
-ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) for conf in (BertConfig, XLNetConfig, XLMConfig, RobertaConfig)), ())
+ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) for conf in (BertConfig, XLNetConfig, XLMConfig, 
+                                                                                RobertaConfig, DistilBertConfig)), ())
 
 MODEL_CLASSES = {
     'bert': (BertConfig, BertForSequenceClassification, BertTokenizer),
@@ -248,7 +249,7 @@ def evaluate(args, model, tokenizer, prefix=""):
         result = compute_metrics(eval_task, preds, out_label_ids)
         results.update(result)
 
-        output_eval_file = os.path.join(eval_output_dir, "eval_results.txt")
+        output_eval_file = os.path.join(eval_output_dir, prefix, "eval_results.txt")
         with open(output_eval_file, "w") as writer:
             logger.info("***** Eval results {} *****".format(prefix))
             for key in sorted(result.keys()):
@@ -489,9 +490,11 @@ def main():
         logger.info("Evaluate the following checkpoints: %s", checkpoints)
         for checkpoint in checkpoints:
             global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            prefix = checkpoint.split('/')[-1] if checkpoint.find('checkpoint') != -1 else ""
+            
             model = model_class.from_pretrained(checkpoint)
             model.to(args.device)
-            result = evaluate(args, model, tokenizer, prefix=global_step)
+            result = evaluate(args, model, tokenizer, prefix=prefix)
             result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
             results.update(result)
 

examples/run_lm_finetuning.py

@@ -59,7 +59,7 @@ class TextDataset(Dataset):
     def __init__(self, tokenizer, file_path='train', block_size=512):
         assert os.path.isfile(file_path)
         directory, filename = os.path.split(file_path)
-        cached_features_file = os.path.join(directory, f'cached_lm_{block_size}_{filename}')
+        cached_features_file = os.path.join(directory, 'cached_lm_{}_{}'.format(block_size, filename))
 
         if os.path.exists(cached_features_file):
             logger.info("Loading features from cached file %s", cached_features_file)
@@ -282,7 +282,7 @@ def evaluate(args, model, tokenizer, prefix=""):
         "perplexity": perplexity
     }
 
-    output_eval_file = os.path.join(eval_output_dir, "eval_results.txt")
+    output_eval_file = os.path.join(eval_output_dir, prefix, "eval_results.txt")
     with open(output_eval_file, "w") as writer:
         logger.info("***** Eval results {} *****".format(prefix))
         for key in sorted(result.keys()):
@@ -484,9 +484,11 @@ def main():
         logger.info("Evaluate the following checkpoints: %s", checkpoints)
         for checkpoint in checkpoints:
             global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            prefix = checkpoint.split('/')[-1] if checkpoint.find('checkpoint') != -1 else ""
+            
             model = model_class.from_pretrained(checkpoint)
             model.to(args.device)
-            result = evaluate(args, model, tokenizer, prefix=global_step)
+            result = evaluate(args, model, tokenizer, prefix=prefix)
             result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
             results.update(result)
 

examples/run_multiple_choice.py

@@ -512,9 +512,11 @@ def main():
         logger.info("Evaluate the following checkpoints: %s", checkpoints)
         for checkpoint in checkpoints:
             global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            prefix = checkpoint.split('/')[-1] if checkpoint.find('checkpoint') != -1 else ""
+            
             model = model_class.from_pretrained(checkpoint)
             model.to(args.device)
-            result = evaluate(args, model, tokenizer, prefix=global_step)
+            result = evaluate(args, model, tokenizer, prefix=prefix)
             result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
             results.update(result)
 
@@ -528,9 +530,11 @@ def main():
         logger.info("Evaluate the following checkpoints: %s", checkpoints)
         for checkpoint in checkpoints:
             global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            prefix = checkpoint.split('/')[-1] if checkpoint.find('checkpoint') != -1 else ""
+            
             model = model_class.from_pretrained(checkpoint)
             model.to(args.device)
-            result = evaluate(args, model, tokenizer, prefix=global_step, test=True)
+            result = evaluate(args, model, tokenizer, prefix=prefix, test=True)
             result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
             results.update(result)
     if best_steps:

examples/run_squad.py

@@ -13,7 +13,7 @@
 # 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.
-""" Finetuning the library models for question-answering on SQuAD (Bert, XLM, XLNet)."""
+""" Finetuning the library models for question-answering on SQuAD (DistilBERT, Bert, XLM, XLNet)."""
 
 from __future__ import absolute_import, division, print_function
 
@@ -135,9 +135,10 @@ def train(args, train_dataset, model, tokenizer):
             batch = tuple(t.to(args.device) for t in batch)
             inputs = {'input_ids':       batch[0],
                       'attention_mask':  batch[1], 
-                      'token_type_ids':  None if args.model_type == 'xlm' else batch[2],  
                       'start_positions': batch[3], 
                       'end_positions':   batch[4]}
+            if args.model_type != 'distilbert':
+                inputs['token_type_ids'] = None if args.model_type == 'xlm' else batch[2]
             if args.model_type in ['xlnet', 'xlm']:
                 inputs.update({'cls_index': batch[5],
                                'p_mask':       batch[6]})
@@ -218,9 +219,10 @@ def evaluate(args, model, tokenizer, prefix=""):
         batch = tuple(t.to(args.device) for t in batch)
         with torch.no_grad():
             inputs = {'input_ids':      batch[0],
-                      'attention_mask': batch[1],
-                      'token_type_ids': None if args.model_type == 'xlm' else batch[2]  # XLM don't use segment_ids
+                      'attention_mask': batch[1]
                       }
+            if args.model_type != 'distilbert':
+                inputs['token_type_ids'] = None if args.model_type == 'xlm' else batch[2]  # XLM don't use segment_ids
             example_indices = batch[3]
             if args.model_type in ['xlnet', 'xlm']:
                 inputs.update({'cls_index': batch[4],

requirements-dev.txt

+absl-py==0.8.0
+astor==0.8.0
+atomicwrites==1.3.0
+attrs==19.2.0
+boto3==1.9.243
+botocore==1.12.243
+certifi==2019.9.11
+chardet==3.0.4
+Click==7.0
+docutils==0.15.2
+gast==0.2.2
+google-pasta==0.1.7
+grpcio==1.24.1
+h5py==2.10.0
+idna==2.8
+importlib-metadata==0.23
+jmespath==0.9.4
+joblib==0.14.0
+Keras-Applications==1.0.8
+Keras-Preprocessing==1.1.0
+Markdown==3.1.1
+more-itertools==7.2.0
+numpy==1.17.2
+opt-einsum==3.1.0
+packaging==19.2
+pluggy==0.13.0
+protobuf==3.10.0
+py==1.8.0
+pyparsing==2.4.2
+pytest==5.2.1
+python-dateutil==2.8.0
+regex==2019.8.19
+requests==2.22.0
+s3transfer==0.2.1
+sacremoses==0.0.35
+sentencepiece==0.1.83
+six==1.12.0
+tensorboard==2.0.0
+tensorflow==2.0.0
+tensorflow-estimator==2.0.0
+termcolor==1.1.0
+torch==1.2.0
+tqdm==4.36.1
+urllib3==1.25.6
+wcwidth==0.1.7
+Werkzeug==0.16.0
+wrapt==1.11.2
+zipp==0.6.0

transformers/configuration_gpt2.py

@@ -28,7 +28,8 @@ logger = logging.getLogger(__name__)
 
 GPT2_PRETRAINED_CONFIG_ARCHIVE_MAP = {"gpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-config.json",
                                       "gpt2-medium": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-medium-config.json",
-                                      "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-config.json"}
+                                      "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-config.json",
+                                      "distilgpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/distilgpt2-config.json",}
 
 class GPT2Config(PretrainedConfig):
     """Configuration class to store the configuration of a `GPT2Model`.

transformers/convert_pytorch_checkpoint_to_tf2.py

@@ -178,10 +178,12 @@ def convert_all_pt_checkpoints_to_tf(args_model_type, tf_dump_path, model_shortc
             else:
                 model_file = cached_path(model_shortcut_name, force_download=not use_cached_models)
 
-            convert_pt_checkpoint_to_tf(model_type,
-                                        model_file,
-                                        config_file,
-                                        os.path.join(tf_dump_path, model_shortcut_name + '-tf_model.h5'),
+            if os.path.isfile(model_shortcut_name):
+                model_shortcut_name = 'converted_model'
+            convert_pt_checkpoint_to_tf(model_type=model_type,
+                                        pytorch_checkpoint_path=model_file,
+                                        config_file=config_file,
+                                        tf_dump_path=os.path.join(tf_dump_path, model_shortcut_name + '-tf_model.h5'),
                                         compare_with_pt_model=compare_with_pt_model)
             os.remove(config_file)
             os.remove(model_file)

transformers/modeling_bert.py

@@ -118,7 +118,7 @@ def load_tf_weights_in_bert(model, config, tf_checkpoint_path):
 
 
 def gelu(x):
-    """ Original Implementation of the gelu activation function in Google Bert repo when initialy created.
+    """ Original Implementation of the gelu activation function in Google Bert repo when initially created.
         For information: OpenAI GPT's gelu is slightly different (and gives slightly different results):
         0.5 * x * (1 + torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3))))
         Also see https://arxiv.org/abs/1606.08415

transformers/modeling_distilbert.py

@@ -159,8 +159,6 @@ class MultiHeadSelfAttention(nn.Module):
 
         dim_per_head = self.dim // self.n_heads
 
-        assert 2 <= mask.dim() <= 3
-        causal = (mask.dim() == 3)
         mask_reshp = (bs, 1, 1, k_length)
 
         def shape(x):
@@ -649,7 +647,7 @@ class DistilBertForQuestionAnswering(DistilBertPreTrainedModel):
         start_positions = torch.tensor([1])
         end_positions = torch.tensor([3])
         outputs = model(input_ids, start_positions=start_positions, end_positions=end_positions)
-        loss, start_scores, end_scores = outputs[:2]
+        loss, start_scores, end_scores = outputs[:3]
 
     """
     def __init__(self, config):

transformers/modeling_gpt2.py

@@ -38,7 +38,8 @@ logger = logging.getLogger(__name__)
 
 GPT2_PRETRAINED_MODEL_ARCHIVE_MAP = {"gpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-pytorch_model.bin",
                                      "gpt2-medium": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-medium-pytorch_model.bin",
-                                     "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-pytorch_model.bin"}
+                                     "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-pytorch_model.bin",
+                                     "distilgpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/distilgpt2-pytorch_model.bin",}
 
 def load_tf_weights_in_gpt2(model, config, gpt2_checkpoint_path):
     """ Load tf checkpoints in a pytorch model

transformers/modeling_tf_bert.py

@@ -62,7 +62,7 @@ def load_bert_pt_weights_in_tf2(tf_model, pytorch_checkpoint_path):
 
 def gelu(x):
     """ Gaussian Error Linear Unit.
-    Original Implementation of the gelu activation function in Google Bert repo when initialy created.
+    Original Implementation of the gelu activation function in Google Bert repo when initially created.
         For information: OpenAI GPT's gelu is slightly different (and gives slightly different results):
         0.5 * x * (1 + torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3))))
         Also see https://arxiv.org/abs/1606.08415

transformers/modeling_tf_distilbert.py

@@ -45,7 +45,7 @@ TF_DISTILBERT_PRETRAINED_MODEL_ARCHIVE_MAP = {
 ### UTILS AND BUILDING BLOCKS OF THE ARCHITECTURE ###
 def gelu(x):
     """ Gaussian Error Linear Unit.
-    Original Implementation of the gelu activation function in Google Bert repo when initialy created.
+    Original Implementation of the gelu activation function in Google Bert repo when initially created.
         For information: OpenAI GPT's gelu is slightly different (and gives slightly different results):
         0.5 * x * (1 + torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3))))
         Also see https://arxiv.org/abs/1606.08415
@@ -226,8 +226,6 @@ class TFMultiHeadSelfAttention(tf.keras.layers.Layer):
 
         dim_per_head = self.dim // self.n_heads
 
-        assert 2 <= len(tf.shape(mask)) <= 3
-        causal = (len(tf.shape(mask)) == 3)
         mask_reshape = [bs, 1, 1, k_length]
 
         def shape(x):
@@ -603,7 +601,7 @@ class TFDistilBertForMaskedLM(TFDistilBertPreTrainedModel):
         tokenizer = DistilBertTokenizer.from_pretrained('distilbert-base-uncased')
         model = TFDistilBertForMaskedLM.from_pretrained('distilbert-base-uncased')
         input_ids = tf.constant(tokenizer.encode("Hello, my dog is cute"))[None, :]  # Batch size 1
-        outputs = model(input_ids, masked_lm_labels=input_ids)
+        outputs = model(input_ids)
         prediction_scores = outputs[0]
 
     """
@@ -715,9 +713,7 @@ class TFDistilBertForQuestionAnswering(TFDistilBertPreTrainedModel):
         tokenizer = DistilBertTokenizer.from_pretrained('distilbert-base-uncased')
         model = TFDistilBertForQuestionAnswering.from_pretrained('distilbert-base-uncased')
         input_ids = tf.constant(tokenizer.encode("Hello, my dog is cute"))[None, :]  # Batch size 1
-        start_positions = tf.constant([1])
-        end_positions = tf.constant([3])
-        outputs = model(input_ids, start_positions=start_positions, end_positions=end_positions)
+        outputs = model(input_ids)
         start_scores, end_scores = outputs[:2]
 
     """

transformers/modeling_tf_gpt2.py

@@ -38,7 +38,8 @@ logger = logging.getLogger(__name__)
 
 TF_GPT2_PRETRAINED_MODEL_ARCHIVE_MAP = {"gpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-tf_model.h5",
                                      "gpt2-medium": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-medium-tf_model.h5",
-                                     "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-tf_model.h5"}
+                                     "gpt2-large": "https://s3.amazonaws.com/models.huggingface.co/bert/gpt2-large-tf_model.h5",
+                                     "distilgpt2": "https://s3.amazonaws.com/models.huggingface.co/bert/distilgpt2-tf_model.h5",}
 
 
 def load_gpt2_pt_weights_in_tf2(tf_model, pytorch_checkpoint_path):