After installing all released versions of python locally, I can confirm that the `python3.15` command is not only very fast, but is guaranteed not to diverge!
$ time python3.15 -c "while True: print('hello world')"
bash: python3.15: command not found
real 0m0.005s
user 0m0.000s
sys 0m0.002s
Jumping 12 major versions to one that doesn't exist yet must yield quite the performance boost.
After installing all released versions of python locally, I can confirm that the `python3.15` command is not only very fast, but is guaranteed not to diverge!