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

首先追蹤 _lsprof 的 profiler_enable 行為及其與 _PyEval_SetProfile 的關係，然後比較 3.11 和 3.12 中 python -m cProfile -m whatever 的行為。檢查 sys.getprofile()、cProfile 和 sys.monitoring 如何互動；當預期的 profiler 物件仍可存取，且不會破壞 3.12+ 的 monitoring 設計時，即表示完成。