Random password generator.

pw.py

#!/usr/bin/env python

import string as s
from random import randint
from sys import argv

CHARS = s.ascii_letters + s.digits + s.punctuation

def main(argc, argv):
    l = 12
    if argc > 1:
        try:
            l = int(argv[1])
        except Exception:
            print("Please enter an integer.")
            exit(-1)
    if l < 4:
        print("Password should contain at least 4 digits.")
        exit(-1)

    pw = ""
    for i in range(0, l):
        pw += CHARS[randint(0, len(CHARS)-1)]

    print(pw)
    exit(0)

if __name__ == "__main__":
    main(len(argv), argv)