string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%BD%91%E9%80%9F%E8%AE%A1%E7%AE%97%E5%8D%95%E4%BD%8D%E5%85%AC%E5%BC%8F => Failed to connect to 101.89.117.144 port 38005: Connection refused"
网速计算单位公式
