docs: def _resource_context(fn):
      """
      Compose path to the ``resources`` directory for given `fn`.
  
      Args:
          fn (str): Filename of file in ``resources`` directory.
  
      Returns:
          str: Absolute path to the file in resources directory.
      """
      return os.path.join(
          os.path.dirname(__file__),
          DES_DIR,
          fn
      )