Python 3.3 was the first version >3 that was actually "good". Prior versions were, if not unusable, not a great experience. Even when writing new code. And some of the Python core devs (Raymond Hettinger) share that opinion.
And let's not understate what a big deal it was to break compatibility like that. Porting a sufficiently complex project is non-trivial.
And let's not understate what a big deal it was to break compatibility like that. Porting a sufficiently complex project is non-trivial.