code: def _get_class_name(model_class: Union[str, List[str]]):
      if isinstance(model_class, (list, tuple)):
          return " or ".join(
              [
                  f":class:`~fastNLP.transformers.torch.{c}`"
                  for c in model_class
                  if c is not None
              ]
          )
      return f":class:`~fastNLP.transformers.torch.{model_class}`"
  
imports: import importlib
  import re
  from collections import OrderedDict
  from typing import List, Union
  from fastNLP.transformers.torch.configuration_utils import PretrainedConfig
  from fastNLP.transformers.torch.file_utils import CONFIG_NAME
  from fastNLP.core.log import logger
label_desc: Use image node_id 3 for calling a global function with example usage: _get_class_name(model_class) and returns: str, model_class, str, str