pyobjc 2.4 dropped support for bridgesupport files, that breaks wrappers for 3th party stuff
Some people have their own framework wrappers, for frameworks that aren't supported by PyObjC or for in-house stuff. These people tend to use tools like gen_bridge_metadata tool generate bridgesupport files.
PyObjC 2.4 dropped support for bridgesupport files and that broke this scenario.
Therefore: reimplement the interface that PyObjC 2.3 used to load metadata files (in pure python, don't reintroduce the dependency on libxml)