code: def channels(self):
          
          if self._channels is None:
              self._channels = ChannelList(self._version, service_sid=self._solution['sid'], )
          return self._channels
docs: Access the channels
  
          :returns: twilio.rest.chat.v2.service.channel.ChannelList
          :rtype: twilio.rest.chat.v2.service.channel.ChannelList