Fabio: "I don't really see a problem in breaking the API in major releases (so, having access for it in the internal API but without a backwards-compatibility guarantee seems like a good fit for me)."
In Python, the internal C API now means that you have to define Py_BUILD_CORE_MODULE macro and include a special "internal/pycore_pystate.h" header file.
If you are fine with doing that in PyCharm, what is the purpose of this issue?
Do you mean in *internal* API or a *private* API? Private API is basically a public API with weaker backward compatibility warranties and with a "_" prefix (_Py, _PY prefix).