Python's platform.python_implementation function is now returning "CPython" instead of "RustPython". I believe it is because Lib/platform.py was refreshed recently (2daddd9) with the latest from CPython, which contains the python_implementation function. Previously, that function (among other things) had been removed from Lib/platform.py back in 2020 (bbb04c3) so that the Rust version of that function in stdlib/src/platform.rs would handle the implementation.

I noticed this because it breaks whats_left.py. (There's a check to make sure the sub-process isn't running CPython, and it now thinks it is, even though it's from "cargo run...".)

I can work on a PR, but I wasn't sure if there's more to this, like other related changes in the works or whatever. If not, I could bascially mimic what was done in bbb04c3. Let me know if I can help.