[deathanatos]

I think _private has always been a convention in Python, though I'd say most Python is not so rigorous about it. I don't see why it couldn't be applied to modules.

I honestly love when I see a package do stuff like this: it's very clear then what is public interface, and I should consider usable (without sin) and what is supposed to be an internal detail.

Same with the modules: then it is very clear that the re-export of those names in __init__.py is where they're meant to be consumed, and the other modules are just for organizational purposes, not API purposes.

_Todo is then a private type.

Very clean.