code: def response(self, apdu):
          
          if _debug: ClientSSM._debug("response %r", apdu)
  
          # make sure it has a good source and destination
          apdu.pduSource = self.pdu_address
          apdu.pduDestination = None
  
          # send it to the application
          self.ssmSAP.sap_response(apdu)
docs: This function is called by client transaction functions when they want
          to send a message to the application.