Update modeling_cvt.py (#17846)

As shown in the colab notebook I added the missing type hints for " CvtForImageClassification
CvtModel
"

src/transformers/models/cvt/modeling_cvt.py

@@ -17,7 +17,7 @@
 
 import collections.abc
 from dataclasses import dataclass
-from typing import Optional, Tuple
+from typing import Optional, Tuple, Union
 
 import torch
 import torch.utils.checkpoint
@@ -604,7 +604,13 @@ class CvtModel(CvtPreTrainedModel):
         modality="vision",
         expected_output=_EXPECTED_OUTPUT_SHAPE,
     )
-    def forward(self, pixel_values=None, output_hidden_states=None, return_dict=None):
+    def forward(
+        self,
+        pixel_values: Optional[torch.Tensor] = None,
+        output_hidden_states: Optional[bool] = None,
+        return_dict: Optional[bool] = None,
+    ) -> Union[Tuple, BaseModelOutputWithCLSToken]:
+
         output_hidden_states = (
             output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
         )
@@ -662,11 +668,11 @@ class CvtForImageClassification(CvtPreTrainedModel):
     )
     def forward(
         self,
-        pixel_values=None,
-        labels=None,
-        output_hidden_states=None,
-        return_dict=None,
-    ):
+        pixel_values: Optional[torch.Tensor] = None,
+        labels: Optional[torch.Tensor] = None,
+        output_hidden_states: Optional[bool] = None,
+        return_dict: Optional[bool] = None,
+    ) -> Union[Tuple, ImageClassifierOutputWithNoAttention]:
         r"""
         labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
             Labels for computing the image classification/regression loss. Indices should be in `[0, ...,