string(248) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%B5%84%E6%9C%AC%E6%80%A7%E6%94%AF%E5%87%BA%E7%9A%84%E7%89%B9%E7%82%B9%E6%98%AF%E4%BB%80%E4%B9%88 => Received HTTP code 403 from proxy after CONNECT"
资本性支出的特点是什么
