string(268) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=3d%E7%94%B5%E5%BD%B1%E8%BF%90%E7%94%A8%E4%BA%86%E5%85%89%E7%9A%84%E4%BB%80%E4%B9%88%E5%8E%9F%E7%90%86 => Failed to connect to 101.91.112.32 port 38162: Connection refused"
3d电影运用了光的什么原理
