code: public GetTagInfoResponse get(Integer tagid){
          GetTagInfoResponse response;
          BeanUtil.requireNonNull(tagid, "tagid不能为空！");
          String url = BASE_API_URL + "cgi-bin/tag/get?access_token=#&tagid=" + tagid;
          BaseResponse r = executeGet(url);
          String jsonResult = isSuccess(r.getErrcode()) ? r.getErrmsg() : r.toJsonString();
          response = JSONUtil.toBean(jsonResult, GetTagInfoResponse.class);
          return response;
      }
docs: 获取标签成员
  @param tagid 目标标签的tagid。不可为空
  @return 标签内信息