[Twisted-Python] Resending a UDP datagram if a response is not received

I am trying to write a client to an existing UDP server that requires a couple of data exchanges before the transaction is complete. Should any of the client's requests go unanswered I would like to resend the request after a timeout period. Perhaps something could be done with reactor.callLater to see if a response had been received but is there a better way to do this? Any pointers/examples would be greatly appreciated. TCP is not an option. Brad