#!/usr/bin/env python3

import secrets
import string
import sys


def generate_password(chars, size):
    return ''.join(secrets.choice(chars) for _ in range(size))


def main():
    size = 20 if len(sys.argv) < 2 else int(sys.argv[1])
    chars = string.ascii_letters + string.digits + string.punctuation

    print(generate_password(chars, size))


if __name__ == "__main__":
    main()