code: def serviceViewChangerOutBox(self, limit: int = None) -> int:
          
          msgCount = 0
          while self.view_changer.outBox and (not limit or msgCount < limit):
              msgCount += 1
              msg = self.view_changer.outBox.popleft()
              if isinstance(msg, (InstanceChange, ViewChangeDone)):
                  self.send(msg)
              else:
                  logger.error("Received msg {} and don't know how to handle it".
                               format(msg))
          return msgCount
docs: Service at most `limit` number of messages from the view_changer's outBox.
  
          :return: the number of messages successfully serviced.