Expose _PyInterpreterFrame_GetLine in the private API

In 3.11 we are using now an opaque pointer to _PyInterpreterFrame in the eval function. The problem is that for PEP 523's APIs, we changed the type of _PyFrameEvalFunction to be PyObject *(*_PyFrameEvalFunction)(PyThreadState *tstate, _PyInterpreterFrame *frame, int throwflag) but there is no way to do anything with _PyInterpreterFrame because is opaque. Even if the extension defines PY_BUILD_CORE the symbols are not exposed in the executable/libpython, which means that including the headers is insufficient.

This is a problem because it really limits what users of PEP 523 can do with the frame object that they receive, even if is opaque. Most profilers using PEP 523 API do it for speed reasons and the only thing they need is to get the line number, but that is now impossible because the pointer is opaque and we don't offer any exposed APIs.

Linked PRs

• gh-96849
• gh-104211
• gh-107188
• gh-107195

Start by reviewing the PEP 523 APIs and the _PyInterpreterFrame and _PyFrameEvalFunction declarations described in the issue. Check the linked PRs gh-96849, gh-104211, gh-107188, and gh-107195 for the current state of the work. Done means profilers can obtain a line number from the opaque frame through an exposed private API.