download vedio resources from youtube
youtube_download.py runs in python3.x, it needs http/https proxy server. It's better to run in window system.
youtube_download.py runs in python3.x, it needs proxychains4 which is able to be downloaded via https://github.com/rofl0r/proxychains-ng. proxychains4 needs one sock5 server.
shadowsocks client sslocal can't provide http/https proxy service in centos 7, but sock5 is OK.