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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 serialize(self, pid, record, links_factory=None, **kwargs):
 """Serialize a single record. :param pid: Persistent identifier instance. :param record: Record instance. :param links_factory: Factory function for record links. """

        data = self.serializer.serialize(pid, record, links_factory)
        source = self._get_source(data)
        style = CitationStylesStyle(validate=False, **self._get_args(**kwargs))
        bib = CitationStylesBibliography(style, source, formatter.plain)
        citation = Citation([CitationItem(pid.pid_value)])
        bib.register(citation)

        return self._clean_result(''.join(bib.bibliography()[0]))