python how to get an on wifi access event

1import socket
2import time
3import subprocess
4
5def check():#this function checks if there is an wifi access
6    try:
7        host = socket.gethostbyname("www.google.com")
8        s = socket.create_connection((host, 80), 2)
9        return True
10    except Exception:
11        return False
12
13      
14while True:#if you want to do something when you get a wifi access so use this loop
15    if check() == True:
16        DoSomeStuff()#whatever you want to do
17    else:
18        subprocess.call(["/bin/bash", "-c", "rfkill", "block", "wifi"])
19        subprocess.call(["/bin/bash", "-c", "rfkill", "unblock", "wifi"])
20        subprocess.Popen(["/bin/bash", "-c", "notify-send 'conncection re-established'"])
21    time.sleep(4)