Fix torch version comparisons (#18460)

Comparisons like
version.parse(torch.__version__) > version.parse("1.6")
are True for torch==1.6.0+cu101 or torch==1.6.0+cpu

version.parse(version.parse(torch.__version__).base_version) are preferred (and available in pytorch_utils.py

templates/adding_a_new_model/cookiecutter-template-{{cookiecutter.modelname}}/modeling_{{cookiecutter.lowercase_modelname}}.py

@@ -22,7 +22,6 @@ import os
 
 import torch
 import torch.utils.checkpoint
-from packaging import version
 from torch import nn
 from torch.nn import BCEWithLogitsLoss, CrossEntropyLoss, MSELoss
 from typing import Optional, Tuple, Union
@@ -48,6 +47,7 @@ from ...pytorch_utils import (
     apply_chunking_to_forward,
     find_pruneable_heads_and_indices,
     prune_linear_layer,
+    is_torch_greater_than_1_6,
 )
 from ...utils import logging
 from .configuration_{{cookiecutter.lowercase_modelname}} import {{cookiecutter.camelcase_modelname}}Config
@@ -157,7 +157,7 @@ class {{cookiecutter.camelcase_modelname}}Embeddings(nn.Module):
         # position_ids (1, len position emb) is contiguous in memory and exported when serialized
         self.register_buffer("position_ids", torch.arange(config.max_position_embeddings).expand((1, -1)))
         self.position_embedding_type = getattr(config, "position_embedding_type", "absolute")
-        if version.parse(torch.__version__) > version.parse("1.6.0"):
+        if is_torch_greater_than_1_6:
             self.register_buffer(
                 "token_type_ids",
                 torch.zeros(self.position_ids.size(), dtype=torch.long, device=self.position_ids.device),