Notify me on Slack when my external IP changes

ip_change_notifier.py

from urllib.request import urlopen
from urllib import request

resp = urlopen("https://api.ipify.org")
ip = resp.read().decode('utf-8').strip()

f = open('last_ip.txt', 'r+')
last_ip = f.read().strip()

if (ip != last_ip):
    f.seek(0)
    f.write(ip)
    f.truncate()
    print(f'Old ip: {last_ip} new ip: {ip}')

    # call webhook
    data_utf8 = f'{{"text": "New IP: *{ip}*"}}'
    data_utf8 = data_utf8.encode('utf-8')
    req =  request.Request('https://hooks.slack.com/services/your_long_string_for_webhooks_here', data=data_utf8)
    resp = request.urlopen(req)

f.close()