how can i get my ip address on my wifi router with python

To get the router that your PC is connected to you can try getting the IP of the default gateway that your PC is using - since your PC will most likely use the router as the default gateway.

Use netifaces for that:

import netifaces

gw = netifaces.gateways()

print(gw['default'][netifaces.AF_INET][0])

Which gives:

192.168.1.1

In my case.

This seems to stop working if you have mapping to 127.0.0.1 in your HOSTS file. Instead I will use getfqdn() (To get fully qualified domain name):

import socket
print(socket.gethostbyname(socket.getfqdn()))