I've attached my two solutions to lab 9. The main two files you should be looking at are simple-game.py, which doesn't use classes (or even our Vector class from lab 8), and game.py (which uses ball.py heavily for all the logic) which uses and extends the classes we designed in lab8.
Even if you didn't get a chance to finish the lab, I recommend checking out the solutions. The first one, at least, is about as simple as I could make it; it runs at about 60 lines of code.
Jeremy Kun
Mathematics Graduate Student
University of Illinois at Chicago