code: func (a *VppAdapter) MockReplyHandler(replyHandler ReplyHandler) {
  	a.repliesLock.Lock()
  	defer a.repliesLock.Unlock()
  
  	a.replyHandlers = append(a.replyHandlers, replyHandler)
  	a.mode = useReplyHandlers
  }
docs: // MockReplyHandler registers a handler function that is supposed to generate mock responses to incoming requests.
  // Using of this method automatically switches the mock into th useReplyHandlers mode.