[Python] Create a Log for your Python application

import sys
import getopt
import logging

# pass in: python3 my_log.py -l info

# Get command line options
# short: l:
# long: [log=]
opts, args = getopt.getopt(sys.argv[1:], "l:", ["log="])

print("opts", opts) #[('-l', 'info')]
print("args", args) #[]

# default log level
log_level="INFO"

for opt, arg in opts: #opt: -l, arg: info
    if opt in ("-l", "--log"):
        log_level = getattr(logging, arg.upper())

logging.basicConfig(filename="./demo.log", level=log_level, format='%(asctime)s %(levelname)s:%(message)s')


for i in range(0, 100):
    if i % 5 == 0:
        logging.debug('Found a number divisible by 5: {0}'.format(i))
    else:
        logging.info('At number {0}'.format(i))

logging.warning('Finished sequence')