As of 3.12 `_lsprof` no longer calls `_PyEval_SetProfile` making `sys.getprofile()` useless with `cProfile`

Bug report

Bug description:

Starting in 3.12 with the addition of sys.monitoring, _lsprof, specifically in profiler_enable, no longer calls _PyEval_SetProfile.

Very specifically, this impacts previous functionality where python -m cProfile -m whatever would result in sys.setprofile() being called, and subsequently the whatever module could access the profiler object via sys.getprofile()

To my knowledge this is now completely impossible as sys.monitoring provides no meaningful way to access the profiler object.

In my particular use case, profiling could be enabled within the application, or if python -m cProfile was used, the existing profiler could be used allowing profiling to happen earlier than the enablement point of cProfile within the application.

Something to the effect of:

p = sys.getprofile()
if p is None:
    p = cProfile.Profile()
    p.enable()

CPython versions tested on:

3.13

Operating systems tested on:

Linux

まず _lsprof の profiler_enable の動作と _PyEval_SetProfile との関係を追跡し、次に 3.11 と 3.12 における python -m cProfile -m whatever の動作を比較します。sys.getprofile()、cProfile、sys.monitoring がどのように連携するかを確認します。3.12 以降の monitoring 設計を壊すことなく、意図された profiler オブジェクトにアクセスできる状態になれば完了です。