Why is Python not portable, as in, on which systems is "build Python and then use that to run Meson" not a reasonable option? The CI for boson seems like it ru

Why is Python not portable, as in, on which systems is "build Python and then use that to run Meson" not a reasonable option? The CI for boson seems like it runs on platforms where Python definitely is available, but also I notice the CI uses samurai, a reimplementation of ninja with a similar motivation: https://github.com/michaelforney/samurai https://github.com/michaelforney/samurai Ninja is in C++ so I am even more confused at Sanurai. Is this just an implementation-diversity thing? (which is great!)