Expose signal-safe way to print stacktraces

[alexmalyshev]

Feature or enhancement

Proposal:

#107215 stopped exporting _Py_DumpTraceback() and _Py_DumpTracebackThreads(). This removed the only signal-safe way of printing a Python stacktrace.

Proposing that they are re-exported.

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• gh-145559: Add PyUnstable_DumpTraceback() and PyUnstable_DumpTracebackThreads() #145560
• gh-145559: Add PyUnstable_DumpTraceback() and PyUnstable_DumpTracebackThreads() #148145