[masklinn]

> I don't think it is nonsensical.

It is completely nonsensical in the context it is made in, the purpose of TFA has nothing to do with the purpose of 2to3, it makes no sense to "rank" them.

> There was a tool 3to2 that took Python 3 code and produced Python 2 code. You had to write in a subset of Python 3 but the idea was sound, I think. Python 3 is more strict in ways than 2 and so downgrading the code was easier (e.g. no implicity str/unicode coercions). It looks like 3to2 is not maintained but I liked the idea.

That still has nothing to do with 2to3, whose intended purpose once again is as a helper for a one-shot conversion of an existing Python 2 project to Python 3.

> If I were writing a library that needed both 2 and 3 compatibility, I would prefer to write Python 3 code and then run 3to2 on it, rather than going the other way.

And guess what? If you're starting from a Python 2 project you can use 2to3 to convert it to Python3 then use some other converter to provide P2 releases.