If you published libraries on pypi you were in exactly that nightmare scenario. How do you support users on both versions of python (because let's be real, it

If you published libraries on pypi you were in exactly that nightmare scenario. How do you support users on both versions of python (because let's be real, it took _ten years_ to change so you had to support both major versions) without two totally separate codebases and all the massive headaches that entails. There were some partial solutions like the library six and all kinds of related tricks to write python that was compatible with both 2 and 3 at the same time.