Verify independence and uniform distribution of discrete values in Python?

[Ethan Furman]

 From Tim Peters:

 > `secrets` is just a wrapper around `random.SystemRandom`, so the
 > presence or absence of `secrets` doesn't matter.
 >
 > As to SystemRandom, all answers depend on the quality of the platform
 > os.urandom(), which Python has no control over. See my answer here,
 > and the comments on it:
 >
 > https://stackoverflow.com/questions/20936993/