string(239) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E4%BA%8C%E5%BB%BA2019%E4%B8%8E2020%E6%95%99%E6%9D%90%E5%8C%BA%E5%88%AB => Failed to connect to 101.89.159.206 port 38075: Connection refused"
二建2019与2020教材区别
