Python 3 support graph for most popular Python libraries and packages http://py3readiness.org
This site utilizes little tool, caniusepython3 created by Brett Cannon.
Throw your requirements.txt file at it and it will tell you which packages support Python 3, and list out which don't.
Please use issue tracker for issues, suggestions, feature requests and further enhancements.
This is derivative work from Python Wheels, a site that tracks progress in new Python package distribution standard called Wheels. All the credits goes to meshy.