Laziness; we already had it installed. That's what a lot of other people are using. It's not that we don't like Python3; their ASTs are considerably simpler (

Laziness; we already had it installed. That's what a lot of other people are using. It's not that we don't like Python3; their ASTs are considerably simpler (e.g. no print statement), they have importlib, and a bunch of other nice things. It's just that the world we interact with mostly uses Python2, so we just follow along.