Here's a backport of the patch to 2.7. It's pretty rad, and basically identical to how YouTube monkeypatches base64.

Not sure what will happen to this patch. According to recent discussion on the list (e.g. https://mail.python.org/pipermail/python-dev/2015-May/140380.html ), performance improvements are open for inclusion in 2.7 if anyone wants to bother with merging this in and taking on the review / maintenance burden.

I'm OK with just publishing it for others to merge in with their own private versions of Python. It is only relevant if you use base64 a lot. :)