Also, it has to fit in < 1 MB, and you won't be able to import anything that uses C extensions. Considering how bloated Python projects are (no dead code elimination whatsoever), I don't expect this to be very usable in practice.
I wonder why they don't target WASM in addition to JS? In the latter case, anything that compiles to WASM would be fair game (I still wouldn't recommend Python in that case, but it would at least be less kludgy for other languages).
cloudflare workers does support wasm! I've written workers in C before and compiled them with emscripten.
Check this one out: I was able to compile the lua interpreter to wasm in order to run lua code on the fly with a worker. It's absolutely a stupid toy but it's still pretty fast, and gives you a decent idea of just how powerful workers can be.
I wonder why they don't target WASM in addition to JS? In the latter case, anything that compiles to WASM would be fair game (I still wouldn't recommend Python in that case, but it would at least be less kludgy for other languages).