[python] How to implement the --verbose or -v option into a script?

There could be a global variable, likely set with argparse from sys.argv, that stands for whether the program should be verbose or not. Then a decorator could be written such that if verbosity was on, then the standard input would be diverted into the null device as long as the function were to run:

import os
from contextlib import redirect_stdout
verbose = False

def louder(f):
    def loud_f(*args, **kwargs):
        if not verbose:
            with open(os.devnull, 'w') as void:
                with redirect_stdout(void):
                    return f(*args, **kwargs)
        return f(*args, **kwargs)
    return loud_f

@louder
def foo(s):
    print(s*3)

foo("bar")

This answer is inspired by this code; actually, I was going to just use it as a module in my program, but I got errors I couldn't understand, so I adapted a portion of it.

The downside of this solution is that verbosity is binary, unlike with logging, which allows for finer-tuning of how verbose the program can be. Also, all print calls are diverted, which might be unwanted for.