code: def messages(self):
          
          if self._messages is None:
              self._messages = MessageList(
                  self._version,
                  service_sid=self._solution['service_sid'],
                  channel_sid=self._solution['sid'],
              )
          return self._messages
docs: Access the messages
  
          :returns: twilio.rest.chat.v1.service.channel.message.MessageList
          :rtype: twilio.rest.chat.v1.service.channel.message.MessageList