code: def progress_bar(self):
      progress_bar = (
          self._progress_bar
          if self._progress_bar is not None
          else Tqdm(**self._tqdm_kwargs)
      )
      return self._stack.enter_context(progress_bar)
  
imports: from contextlib import ExitStack
  from typing import TYPE_CHECKING, Any, BinaryIO, Dict, Optional, Union
  from dvc.progress import Tqdm
  from dvc.utils.objects import cached_property
  from dvc_objects.fs.callbacks import DEFAULT_CALLBACK, Callback
label_desc: Use image node_id 2 for calling the TqdmCallback obj's underlying member method code with example usage: obj.progress_bar() and returns: self