Python logging argparse utility for controlling logging level

example.py

from . import logging
from .logging import log

def main(args):
    # set up logging from the arguments
    logging.init(args)
    log.info("hello world!")


if __name__ == "__main__":
    parser = ArgumentParser()
    # define your arguments here and then
    # add the `-v` option to the argument parser
    logging.add_argument(parser)
    
    main(parser.parse_args())
    

logging.py

import logging
from argparse import ArgumentParser, Namespace

log = logging


def init(args: Namespace):
    logging.basicConfig(format='%(asctime)s %(module)s %(levelname)s: %(message)s')
    levels = [logging.ERROR, logging.WARNING, logging.INFO, logging.DEBUG]
    if args.verbosity >= len(levels):
        raise IndexError("Verbosity must be 0 <= n < 4")
    logging.getLogger().setLevel(levels[args.verbosity])


def add_argument(parser: ArgumentParser):
    parser.add_argument("-v", dest="verbosity", action="count", default=0,
                        help="Control verbosity")