string(240) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%B8%AD%E7%BA%A7%E7%8F%AD%E6%98%AF%E4%BB%80%E4%B9%88%E6%96%87%E5%87%AD => Failed to connect to 101.89.159.206 port 38100: Connection refused"
中级班是什么文凭
