From Jeff Bauer's recipe.

# server.py
import socket
port = 8081
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind(("", port))
print "waiting on port:", port
while 1:
    data, addr = s.recvfrom(1024)
    print data


# client.py
import socket
port = 8081
host = "localhost"
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind(("", 0))
s.sendto("Holy Guido! It's working.", (host, port))