UUIDv4

I was in need of using a quick UUIDv4 to use as a token but I had no internet, so I had to write a short one

import secrets

def uuidv4():
    r = secrets.randbits
    return ''.join(
        f"{r(4):x}" if c=='x' else f"{((r(4)&3)|8):x}" if c=='y' else c
        for c in 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'
    )

really simple and small. And it works!