We're pretty conservative with the things we add, it's 95% correcting comments/documentation and the other 5% minor (behavior-preserving) transformations. We w

We're pretty conservative with the things we add, it's 95% correcting comments/documentation and the other 5% minor (behavior-preserving) transformations. We work in Python, so those transformations are things like using `collections.defaultdict` instead of a plain dictionary where it makes sense etc etc.