Really? In my experience, dealing with the changes to Unicode handling are usually the sole non trivial change when handling py2k and 3k from the same codebase.

Really? In my experience, dealing with the changes to Unicode handling are usually the sole non trivial change when handling py2k and 3k from the same codebase. Everything else is just a case of either import six, or writing a little (sub 50 line) compat module. Of course, I imagine things get more interesting if you fiddle with cpython internals a lot, but those cases are in the minority.