import os
import requests
import time

while True:
    os.system('dhclient -r && rm -f /var/lib/dhcp/dhclient.leases && dhclient -v');
    try:
        requests.get('http://baidu.com', timeout=5)
        print('IP Working! Script Stop, please check IP !!')
        exit()
    except Exception:
        print('IP not working, keep trying...' )
    time.sleep(5)