code: def __getitem__(self, key: int | slice) -> str:
      warnings.warn(
          "The str interface for _CascadingStyleSheet objects is deprecated. "
          "Use css.filename instead.",
          RemovedInSphinx90Warning,
          stacklevel=2,
      )
      return os.fspath(self.filename)[key]
  
imports: from __future__ import annotations
  import os
  import warnings
  import zlib
  from typing import TYPE_CHECKING, Any, NoReturn
  from sphinx.deprecation import RemovedInSphinx90Warning
  from sphinx.errors import ThemeError
label_desc: Use image node_id 8 for calling the _CascadingStyleSheet obj's underlying member method code with example usage: obj.__getitem__(key) and returns: os