[$] Python's two modules for random numbers
Python's random and secrets modules both include utilities for obtaining random values, but only one of them is suitable for generating passwords and security tokens. For much of Python's history, random was used for passwords and tokens anyway, despite documentation that called it unsuitable for cryptography. In 2015, Python's core team debated whether to fix that misuse by making random secure…
We haven't written up this one. LWN has the full story — the link below goes straight to it.