code: def to_xml(el):
      
      sio = StringIO()
      el.export(sio, 0, name_='PcGts', namespacedef_='xmlns:pc="%s"' % NAMESPACES['page'])
      return '<?xml version="1.0" encoding="UTF-8"?>\n' + sio.getvalue()
docs: Serialize ``pc:PcGts`` document