Hi,
i needed this method for my game, so i patched pygame. see attachment. unfortunatly my makeref.py crashes, so i had to modify src/doc/gfxdraw_doc.h manually (i did not include this in the patch).
the new function is more or less identical with the old for pie(), i simple made it with copy&paste. i think there could be a better solution with a function for both, but so far this worked for me.
would be nice to see the new method in an official version.