We've had a binding/platform for the Off-Screen Mesa (OSMesa) library for a while now. It was originally coded such that it provided all of the OSMesa entry points from the platform package (not really appropriate, as these are the same level as things such as GLX and WGL). Long story short, they've been moved to OpenGL/osmesa instead. Code that uses OSMesa in PyOpenGL can just update the imports to

# from OpenGL.platform import *
from OpenGL.osmesa import *

to get the entry points that have moved.