run_client.py

import socket
import struct
import sys

multicast_group = '224.3.29.71'
server_address = ('', 10000)

# Create the socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

# Bind to the server address
sock.bind(server_address)

# Tell the operating system to add the socket to the multicast group
# on all interfaces.
group = socket.inet_aton(multicast_group)
mreq = struct.pack('4sL', group, socket.INADDR_ANY)
sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)

while True:
    print("waiting")

    data, address = sock.recvfrom(1024)
    msg = bytes.decode(data)
    print("Message: " + msg + "\n")
    print("Address:" + address[0] + "\t From Port: " + str(address[1]))
    print("sending reply")
    sock.sendto("ack".encode(), address)