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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 oaiid_fetcher(record_uuid, data):
 """Fetch a record's identifier. :param record_uuid: The record UUID. :param data: The record data. :returns: A :class:`invenio_pidstore.fetchers.FetchedPID` instance. """

    pid_value = data.get('_oai', {}).get('id')
    if pid_value is None:
        raise PersistentIdentifierError()
    return FetchedPID(
        provider=OAIIDProvider,
        pid_type=OAIIDProvider.pid_type,
        pid_value=str(pid_value),
    )