string(274) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E9%94%85%E7%82%89%E5%B7%A5%E7%9A%84%E8%81%8C%E8%B4%A3%E5%92%8C%E4%BB%BB%E5%8A%A1%E6%98%AF%E4%BB%80%E4%B9%88 => Failed to connect to 14.18.117.71 port 38220: Connection refused"
锅炉工的职责和任务是什么
