I agree that it makes no sense to define __file__ for frozen modules. Originally they did because that was the only way to tell if a module was a builtin module or not, but with the imp module's API on top of sys.builtin_module_names, there is no need to maintain this invariant.

As for site.py requiring the module to have a __file__ on os, I think that is somewhat bogus as well and should be optional so issue (3) for Meador should be to patch site.py to not flat-out require os.__file__ exist.