DNS test in Python

dnstest.py

#!/usr/bin/python3

import argparse
import socket
import logging
import time

def parse_arguments():
    parser = argparse.ArgumentParser(description='DNS test')
    parser.add_argument('-w', '--wait', default=0.5,
                        help='wait time', type=float)
    parser.add_argument('host', help='host to resolve')
    return parser.parse_args()


def main(opts):
    while True:
        try:
            res = socket.getaddrinfo(opts.host, None)
        except socket.gaierror as err:
            logging.error('resolver failed: %s', err)
        else:
            addrs = {v[4][0] for v in res}
            logging.info('resolved to: %s', addrs)
        time.sleep(opts.wait)


if __name__ == '__main__':
    opts = parse_arguments()
    logging.basicConfig(level=logging.DEBUG,
                        format='%(asctime)s - %(levelname)s - %(message)s')
    main(opts)