Multiuser Chatting using UDP Socket

Program :

Server Side :

import random
from socket import *
from threading import Thread, Lock

client_info = {}

def receiver(serverSocket):
	global client_info
	global recv_msg
	global name
	while flag:
		#print "started"
		recv_msg, address = serverSocket.recvfrom(1024)
		#print bool(client_info)
		if bool(client_info):
			if address in client_info.keys():
				msg = "\t\t"+client_info[address]+":"+recv_msg
				print msg
				for addr in client_info:
					'''Send data using sendto to addr'''	
			else:
				client_info[address] = recv_msg
				msg = "\n"+str(client_info[address])+" is online"
				print msg
				for addr in client_info:
					'''Send data using sendto to addr'''	
		else:
			client_info[address] = recv_msg
			msg = "\n"+str(client_info[address])+" is online"
			print msg
			for addr in client_info:
				'''Send data using sendto to addr'''	
		
		



flag = True
serverSocket = socket(AF_INET, SOCK_DGRAM)
serverSocket.bind(('', 12000))


#recv_msg, address = serverSocket.recvfrom(1024)
#client_addr = str(address[0])
#print recv_msg + "is connected from IP:"+str(address[0])+" and Port:"+str(address[1])+"\n"
#name = recv_msg

# Start channel receiver thread
'''Create a thread and call listener'''
recv_thread.daemon = True
recv_thread.start()
print "Server Started Listening.."

while flag:
	send_msg = raw_input()
	
	if send_msg == '*quit*':
		flag = False
		serverSocket.sendto(send_msg, address)
	else:
		serverSocket.sendto(send_msg, address)

Client Side :

from socket import *
import time
from threading import Thread, Lock

def receiver(clientSocket):
	global recv_msg
	while flag:
		'''receive data from server'''
		print "\t\t"+recv_msg

flag = True

clientSocket = socket(AF_INET, SOCK_DGRAM)
addr = ('127.0.0.1', 12000)
name = str(raw_input("Enter Your Name:"))

'''Send name to client'''
#try:
	
# Start channel receiver thread
recv_thread = Thread(target=receiver, args=(clientSocket,))
recv_thread.daemon = True
recv_thread.start()

recv_msg = 'NUll'

while recv_msg != '*quit*':
	send_msg = raw_input()
	if send_msg == '*quit*':
		'''Send the data'''
		flag = False
		recv_thread.stop()
	else:
		'''Send the data'''