string(255) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%9F%BA%E5%B0%BC%E7%B3%BB%E6%95%B0%E5%A4%A7%E5%B0%8F%E8%A1%A8%E7%A4%BA%E4%BB%80%E4%B9%88 => Failed to connect to 14.18.46.51 port 38206: Connection refused"
基尼系数大小表示什么
