def GetParentFileEntry(self):
    """Retrieves the parent file entry.

    Returns:
      OSFileEntry: parent file entry or None if not available.
    """
    location = getattr(self.path_spec, 'location', None)
    if location is None:
      return None

    parent_location = self._file_system.DirnamePath(location)
    if parent_location is None:
      return None

    if parent_location == '':
      parent_location = self._file_system.PATH_SEPARATOR

    path_spec = os_path_spec.OSPathSpec(location=parent_location)
    return OSFileEntry(self._resolver_context, self._file_system, path_spec)
Retrieves the parent file entry.

    Returns:
      OSFileEntry: parent file entry or None if not available.