Get rtsp youtube link

I read a number of answers like this , this and this

But these ALL link to http://gdata.youtube.com/feeds/api/videos/VIDEO_ID

which is no longer available . I want play and download youtube video

android. But I faced several problems, for example, it is youtube

banned in our country. So it doesn't work.What the latest way of doing this.

So how can I play and download a YouTube video using its URL?