Using a copyrighted music track as the example in the README is really stupid or just shows a total lack of respect for copyright.
The DMCA is complaining about test cases. See extractor/youtube.py in your local copy.
The stupid thing is hosting youtube-dl in the Untied States.
It's not like a million people don't have youtube-dl's source code.
It can be hosted anywhere in the world in a heartbeat, and by now probably has been a thousand times over.