2020
https://realpython.com/python-namespaces-scope/
    https://nuancesprog.ru/p/9211/
????
http://www.artima.com/weblogs/viewpost.jsp?thread=4829

def main(args):
    try:
        ...
    except:
        ...
        sys.exit(1)

if __name__ == '__main__':
    import sys
    main(sys.argv)