Use python3 hashbang in scripts #477
Description
As per https://peps.python.org/pep-0394/, the naming of the Python interpreter on Linux is a bit of a mess.
Notably, whilst all distros have python3, not all distros have python.
Thus it seems sensible to change all the hashbangs to #! /usr/bin/env python3 as they are python3 scripts and who knows what happens to python when python4 is released, if that ever happens!