The latest version is Python 3.8.4, and if I search for “Python” on my Windows computer, I see that I have Python 3.6 and 3.5 – so I could do with an update! That is how to check Python version!

Try running this program with Python 3.12 or Python 3.13 (the GIL version). On my AMD Ryzen 3600 six-core machine, it completes in about two seconds. With Python 3.13t, it completes in about 0.6 ...