import argparse

parser = argparse.ArgumentParser(description='Process some integers.')
parser.add_argument('integers', metavar='N', type=int, nargs='+',
                    help='An integer for the accumulator.')
parser.add_argument('-i', '--identity', type=int, default=0,
                    help='the default result for no arguments '
                         '(default: 0)')
parser.add_argument('--sum', dest='accumulate', action='store_const',
                    const=sum, default=max,
                    help='Sum the integers (default: find the max).')

if __name__ == '__main__':
    args = parser.parse_args()
    print(args.accumulate(args.integers))