string(238) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E6%95%B0%E6%8D%AE%E5%8F%AF%E8%A7%86%E5%8C%96%E7%9A%84%E5%8E%9F%E7%90%86 => Failed to connect to 14.18.117.71 port 38133: Connection refused"
数据可视化的原理
