zlacker

That distinction is indeed critical, and I'm not suggesting removing that distinction. My point is that you could give all those types names, and manage the transition by having Python 3 change the defaults (e.g. that a string is unicode).

>>JoshTr+(OP)
I’m a little confused. That’s basically with Python 3 did, right? In py2, “foo” is a string of bytes, and u”foo” is Unicode. In py3, both are Unicode, and bytes() is a string of bytes.

>>kstrau+M
The difference is that the two don't interoperate. You can't import a Python 3 module from Python 2 or vice versa; you have to use completely separate interpreters to run them.

I'm suggesting a model in which one interpreter runs both Python 2 and Python 3, and the underlying types are the same, so you can pass them between the two. You'd have to know that "foo" created in Python 2 is the equivalent of b"foo" created in Python 3, but that's easy enough to deal with.