code: def machine_to_machine(self):
          
          if self._machine_to_machine is None:
              self._machine_to_machine = MachineToMachineList(
                  self._version,
                  account_sid=self._solution['account_sid'],
                  country_code=self._solution['country_code'],
              )
          return self._machine_to_machine
docs: Access the machine_to_machine
  
          :returns: twilio.rest.api.v2010.account.available_phone_number.machine_to_machine.MachineToMachineList
          :rtype: twilio.rest.api.v2010.account.available_phone_number.machine_to_machine.MachineToMachineList