I can point you to two places:

1. http://pythonmentors.com/ This will solve the mentor-ship problem you have. Folks in the core and around who are mentors will listen to your problems and can help you on the way. Although they are very nice with newbies, please make sure that you try to be as clear and professional in your approach/questions as possible.

2. http://openhatch.org/ This website gives you small, medium and tough level of bugs in most of the prominent opensource projects.

Hope this helps.