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

首先跟踪 _lsprof 的 profiler_enable 行为及其与 _PyEval_SetProfile 的关系，然后比较 3.11 和 3.12 中 python -m cProfile -m whatever 的行为。检查 sys.getprofile()、cProfile 和 sys.monitoring 如何交互；当预期的 profiler 对象仍可访问且不会破坏 3.12+ 的 monitoring 设计时，即视为完成。