def GetRootFileEntry(self):
    """Retrieves the root file entry.

    Returns:
      CPIOFileEntry: a file entry or None if not available.
    """
    path_spec = cpio_path_spec.CPIOPathSpec(
        location=self.LOCATION_ROOT, parent=self._path_spec.parent)
    return self.GetFileEntryByPathSpec(path_spec)
Retrieves the root file entry.

    Returns:
      CPIOFileEntry: a file entry or None if not available.