def transform_to_mods_mono(marc_xml, uuid, url):
    """
    Convert `marc_xml` to MODS data format.

    Args:
        marc_xml (str): Filename or XML string. Don't use ``\\n`` in case of
                        filename.
        uuid (str): UUID string giving the package ID.
        url (str): URL of the publication (public or not).

    Returns:
        list: Collection of transformed xml strings.
    """
    marc_xml = _read_content_or_path(marc_xml)

    transformed = xslt_transformation(
        marc_xml,
        _absolute_template_path("MARC21slim2MODS3-4-NDK.xsl")
    )

    return _apply_postprocessing(
        marc_xml=marc_xml,
        xml=transformed,
        func=mods_postprocessor.postprocess_monograph,
        uuid=uuid,
        url=url,
    )
Convert `marc_xml` to MODS data format.

    Args:
        marc_xml (str): Filename or XML string. Don't use ``\\n`` in case of
                        filename.
        uuid (str): UUID string giving the package ID.
        url (str): URL of the publication (public or not).

    Returns:
        list: Collection of transformed xml strings.