Suggestion for challenge
I have good idea.
We can have challenge where we must select game from pyweek 18 (which isn't your) and change it and upgrade.
It should encourage code reading, error handling(probably when you try to change something in other's game there might be more errors than when you change something in your game) and thinking(like in normal pyweek).
The most things should be same as in normal pyweek.
Please leave comment and write what you think about it.