Message 380273 - Python tracker

When working in a C extension from a non-python created thread which calls PyGILState_Ensure as it later calls a Python callback on user code, I wished there was a way to set the trace function similar to what a native Python thread would do.

We could just call sys.gettrace within the thread, but the application might have chosen to set threading.settrace differently.

Same applies for threading.setprofile.