None of the things you mentioned are particularly difficult though. In fact you're still in the realm of changes that can be trivially automated with https://python-modernize.readthedocs.io/en/latest/fixers.htm..., the three issues you describe are the print, xrange_six, and classic_division fixers.
It's certainly possible that there are parts of the migration that would be tricky, a quick skim of the file didn't give me any obvious ones, but it's also huge and hard to read, so I very well could have missed something.
Most of the truly challenging things to migrate involved some combination of extension modules, heavy metaprogramming (eval/exec), and apis which change significantly between 2 and 3 (most of which are string related, but some libraries also decided to do backwards incompatible things)
It's certainly possible that there are parts of the migration that would be tricky, a quick skim of the file didn't give me any obvious ones, but it's also huge and hard to read, so I very well could have missed something.
Most of the truly challenging things to migrate involved some combination of extension modules, heavy metaprogramming (eval/exec), and apis which change significantly between 2 and 3 (most of which are string related, but some libraries also decided to do backwards incompatible things)