简洁的panic recover代码：
https://www.cnblogs.com/songxingzhu/p/5255485.html
https://www.cnblogs.com/baiyuxiong/p/4770980.html
panic recover error 几个概念的说明:
https://blog.csdn.net/wuwenxiang91322/article/details/9042503
异常处理的几个例子：
https://www.jianshu.com/p/f30da01eea97
