code: public boolean addQuickReply(QuickReply quickReply) {
      if (quickReplies == null) {
        quickReplies = new ArrayList<>();
      }
  
      checkPrecondition(1);
  
      return quickReplies.add(quickReply);
    }
docs: add single {@code QuickReply} to the list of QuickReplies
  
  @param quickReply
  the QuickReply you like to add
  @return