PyPy

[dogtopus]

So far ffsds4 runs under PyPy but with some caveats:

1. New typing features (e.g. Protocols) are not supported in PyPy due to the lower targeted API level (3.7). This can be resolved once they releases a new version that supports API level 3.8 (which should be the actual minimum required version for ffsds4).
2. The performance is really bad, with the DS4Function thread @ 250 FPS using 20% of CPU on not-so-bad-and-still-better-than-most-maker-grade-ARM x86 processor (!) and Sequencer thread running hotter than CPython most of the time. Profiling might be required once 1 is resolved.
3. No PyInstaller support (for obvious reasons). Just live with it I guess.

If 2 can be resolved, maybe it' possible to list PyPy as supported.