code: def participants(self):
          
          if self._participants is None:
              self._participants = ParticipantList(
                  self._version,
                  account_sid=self._solution['account_sid'],
                  conference_sid=self._solution['sid'],
              )
          return self._participants
docs: Access the participants
  
          :returns: twilio.rest.api.v2010.account.conference.participant.ParticipantList
          :rtype: twilio.rest.api.v2010.account.conference.participant.ParticipantList