code: def confsponsor(self):
          
          sponsors = chained_get(self._confevent, ['confsponsors', 'confsponsor'], [])
          if len(sponsors) == 0:
              return None
          if isinstance(sponsors, list):
              return [s['$'] for s in sponsors]
          return sponsors
docs: Sponsor(s) of the conference the abstract belongs to.