Method to send a discovery message

def discover(self):
        """Method to send a discovery message
        """
        if self.transport:
            if self.discovery_countdown <= 0:
                self.discovery_countdown = self.discovery_interval
                msg = GetService(BROADCAST_MAC, self.source_id, seq_num=0, payload={}, ack_requested=False, response_requested=True)
                self.transport.sendto(msg.generate_packed_message(), (self.broadcast_ip, UDP_BROADCAST_PORT))
            else:
                self.discovery_countdown -= self.discovery_step
            self.loop.call_later(self.discovery_step, self.discover)