Recently a Python developer friend with whom I was pair programming with suggested that I show him how to write a little Ruby. I responded by telling him to check out Ruby Koans as a starting point.
However I wanted to try that in reverse at the same time with me learning some Python. I did a bit of googling, and sure enough someone had started writing some Python Koans. It just needed finishing...
So, a few weeks later Python Koans is now complete and ready for action!
It is available through Mercurial on Bitbucket:
http://bitbucket.org/gregmalcolm/python_koans/wiki/Home
It is also mirrored on Github:
http://wiki.github.com/gregmalcolm/python_koans/
Converting it was fairly easy. Aside from the differing philosophical approaches behind the two languages, Ruby and Python are fairly similar. We had to come up with completely new material for a few subjects like multiple inheritance and decorators, but for most features in Ruby there is something roughly comparable in Python.
I highly recommend writing tests (or koans) as a means to lean a new language or framework. I've learned a lot from doing this.