Whilst looking at some old code of mine, I discovered a quick way to
programmatically retrieve a hosts local IP address, the
socket.getsockname() function.
To get the local IP address, create a UDP socket (see socket.SOCK_DGRAM
below), connect to an arbitrary server (this can be local or remote, such
as google.com) and run the getsockname() function on the socket.
This returns a tuple and the first item in that tuple is the hosts local IP address. Easy.
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.connect(('google.com', 80))
ip, _ = sock.getsockname()
sock.close()
print(ip)
# 192.168.1.2