[oblio]

This usually madness for production projects, unless you're Apple (or Microsoft in the 90s).

But I wish Python 3 did the same with its libraries.

[masklinn]

Python 3 did implement pretty significant library changes, though mostly organisational (namespace restructuring, merging of C accelerator modules, renamings, removal of deprecated modules, …): https://www.python.org/dev/peps/pep-3108/