code: def __enter__(self) -> IO[Any]:
      return self.tempfile()
  
file_path: optuna/optuna/testing/tempfile_pool.py
imports: from __future__ import annotations
  import atexit
  import gc
  import os
  import tempfile
  from types import TracebackType
  from typing import Any
  from typing import IO
label_desc: Use image node_id 5 for calling the NamedTemporaryFilePool obj's underlying member method code with example usage: obj.__enter__() and returns: self