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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _oai_to_xml(marc_oai):
 # TODO: move this to MARC XML parser? """ Convert OAI to MARC XML. Args: marc_oai (str):
 String with either OAI or MARC XML. Returns: str: String with MARC XML. """

    record = MARCXMLRecord(marc_oai)
    record.oai_marc = False

    return record.to_XML()