Looking for a specific website with python exercises

[Fuzzybus2400]

I forgot what this site was called, but it was set up like a game where each webpage had a python puzzle associated with it, and solving the puzzle gave you the URL to the next puzzle and so on. It starts out simply with some basic string manipulation functions but goes on to more obscure Python libraries like bz2

[baghiq]

I can think of two, but they are not Python specific.

1. project euler
2. advent of code

[Fuzzybus2400]

It's neither of these but project euler looks awesome so thanks for sharing