#!/usr/bin/env python

# coding=utf-8

import argparse

parser = argparse.ArgumentParser(prog="myprogram ",description="a test of argparse")

parser.add_argument("-a",type=int,dest="start",choices={1,2,3},help="start number")

parser.add_argument("-b",type=int,dest="end",help="end point")

parser.add_argument("-s","--sum",dest="data",required=True,type=int,nargs="*",help="numbers to add")

parser.add_argument("-o",required=True,dest="fw",help="output file")

def cal_sum(a,b):

    s = 0

    for i in range(a,b):

        s += i

    return s

if __name__=="__main__":

    args = parser.parse_args()

    print args

    print vars(args)

    data = args.data

    print sum(data)

    res = str(sum(data))

    with open(args.fw,'wb') as fw:

        fw.write(res)

>：~/$ python util.py -s 1 2 3 -o output.txt

Namespace(data=[1, 2, 3], end=None, fw='output.txt', start=None)

{'start': None, 'fw': 'output.txt', 'end': None, 'data': [1, 2, 3]}

6

jkmiao@jkmiao-ipin:~/workplace/mygithub/leetcodex$ more output.txt

6