code: def last_month(self):
          
          if self._last_month is None:
              self._last_month = LastMonthList(self._version, account_sid=self._solution['account_sid'], )
          return self._last_month
docs: Access the last_month
  
          :returns: twilio.rest.api.v2010.account.usage.record.last_month.LastMonthList
          :rtype: twilio.rest.api.v2010.account.usage.record.last_month.LastMonthList