code: def smtp_msgdata(self):
          
          msg_data = self.arguments()
          self._command_parser.switch_to_command_mode()
          self._check_size_restrictions(msg_data)
          decision, response_sent = self.is_allowed('accept_msgdata', msg_data, self._message)
          if decision:
              self._message.msg_data = msg_data
              new_message = self._copy_basic_settings(self._message)
              self._deliverer.new_message_accepted(self._message)
              if not response_sent:
                  self.reply(250, 'OK')
                  # Now we must not loose the message anymore!
              self._message = new_message
          elif not decision:
              raise PolicyDenial(response_sent, 550, 'Message content is not acceptable')
docs: This method handles not a real smtp command. It is called when the
          whole message was received (multi-line DATA command is completed).