string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%97%B6%E9%97%B4%E5%BA%8F%E5%88%97%E5%B8%B8%E7%94%A8%E6%A8%A1%E5%9E%8B => Failed to connect to 101.89.159.206 port 38100: Connection refused"
时间序列常用模型
