def _display_nightly_str(nightly_doc_util, builder):
  """Header nightly note section."""
  if nightly_doc_util.is_builder_nightly(builder):
    return f"""\
      Note: This dataset was added recently and is only available in our
      `tfds-nightly` package  {nightly_doc_util.icon}.
      """
  elif nightly_doc_util.has_nightly(builder):
    return f"""\
      Note: This dataset has been updated since the last stable release.
      The new versions and config marked with {nightly_doc_util.icon}
      are only available in the `tfds-nightly` package.
      """
  else:
    return ''