string(239) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%9F%AD%E8%B7%AF%E5%92%8C%E6%96%AD%E8%B7%AF%E7%9A%84%E5%8C%BA%E5%88%AB%E5%88%A4%E6%96%AD => Received HTTP code 403 from proxy after CONNECT"
短路和断路的区别判断
