string(276) "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%E5%88%A9%E7%94%A8%E7%9A%84%E6%98%AF%E5%85%89%E7%9A%84%E4%BB%80%E4%B9%88%E7%8E%B0%E8%B1%A1 => Failed to connect to 14.18.117.71 port 38220: Connection refused"
3d电影利用的是光的什么现象
