string(246) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=2000kg%E7%AD%89%E4%BA%8E%E5%A4%9A%E5%B0%91%E6%96%A4%E5%A4%9A%E5%B0%91%E5%90%A8 => Failed to connect to 101.89.159.206 port 38187: Connection refused"
2000kg等于多少斤多少吨
