from socket import *

 from time import ctime

 host = ''

 port = 21567

 buf_size = 1024

 addr = (host, port)

 udpSerSock = socket(AF_INET, SOCK_DGRAM)

 udpSerSock.bind(addr)

 while True:

     print("waiting for message...")

     data, ADDR = udpSerSock.recvfrom(buf_size)

     response = '[%s] %s' % (ctime(), data.decode('utf-8'))

     udpSerSock.sendto(response.encode('utf-8'), ADDR)

     print("...received from and returned to:", ADDR)

 udpSerSock.close()

 from socket import *

 host = 'localhost'

 port = 21567

 buf_size = 1024

 addr = (host, port)

 udpCliSock = socket(AF_INET, SOCK_DGRAM)

 while True:

     data = input('>')

     if not data:

         break

     udpCliSock.sendto(data.encode('utf-8'), addr)

     data, addr = udpCliSock.recvfrom(buf_size)

     if not data:

         break

     print(data.decode('utf-8'))

 udpCliSock.close()