Pythonによるマルチスレッドチャット機能

#-*- coding:utf-8 -*-
from threading import Thread
from socket import *
#1. 
def recvDate():
    while True:
        recvInfo = udpSocket.recvfrom(1024)
        print("\r
>>%s:%s"%(str(recvInfo[1]),recvInfo[0].decode("gb2312")))
        print("<)

#2. 
def sendDate():
    while True:
        sendInfo = input("<)
        udpSocket.sendto(sendInfo.encode("gb2312"),(destIp,destPort))

udpSocket = None
destIp = ""
destPort = 0

def main():
    # global
    global udpSocket
    global destIp
    global destPort

    udpSocket = socket(AF_INET, SOCK_DGRAM)


    destIp = input(" ip:")
    destPort = int(input(" :"))
    localPort = int(input(" :")) 
    udpSocket.bind(("",localPort))  # 
    re = Thread(target = recvDate)  # 1
    rh = Thread(target = sendDate)  # 2

    re.start()
    rh.start()

    re.join() # 
    rh.join()

if __name__ == "__main__":
    main()