Oh yes I've been wondering about that too. I think what tipped me off about the feature is that I debugged some code using yacc, and it jumped right to the .y file. So yacc does that pretty effectively.
So I think that would be cool, but I don't usually use a debugger in Python (or even C++ -- I tend to write small programs using shell as the "REPL").
Oil is extremely test-driven and shell's stdin/stdout type interfaces means it's pretty easy to exhaustively test. Examples: https://www.oilshell.org/release/0.13.1/test/spec.wwz/survey...
The GC is the one case we have where that kind of testing/debugging doesn't suffice! So I started watching the CppCon videos on debuggers a couple years ago and found some good talks :)