string(239) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%B4%BE%E5%B2%9B%E6%8E%A8%E6%95%B2%E7%BB%99%E6%88%91%E4%BB%AC%E7%9A%84%E5%90%AF%E7%A4%BA => Received HTTP code 403 from proxy after CONNECT"
贾岛推敲给我们的启示
