def publish_function(self):
        # save all futures so we can wait for them to complete
        # Callbacks receive the future as their only argument, as defined in
        # the Future interface.
        def callback(future):
            message_id = future.result()
            self.logger.debug(f"Sent message: {message_id}")

        # The callback is added once you get the future. If you add a callback
        # and the future is already done, it will simply be executed immediately.
        future = self.publisher.publish(self.topic_path, data=self.message)
        print(future)
        future.add_done_callback(callback)
        self.results.append(future)

    def publish(self, total_messages, messages_per_second):
        i = 0
        sleep_time = 1
        if messages_per_second < 1:
            sleep_time = float(sleep_time) / float(messages_per_second)
        logger.debug(f"Sleep time is: {sleep_time}")
        while i < total_messages and not self.exit:
            start = time.time()
            # number of times to send per second
            # if less than one, then the sleep timer handles the wait. We just send one message here
            for j in range(int(math.ceil(messages_per_second))):
                self.publish_function()
                i += 1
                self.next_id()
                # exit inner loop if we hit the total to send
                if i >= total_messages or self.exit:
                    self.stop()
                    break

            # apply result to all futures in self.results. This blocks until the future it's called on completes
            # list forces the map to execute since map returns an iterable


            list(map(futures.Future.result, self.results)) <<<<<<<<<<<--------- ***HANGS HERE***

            end = time.time()
            logger.info(
                f"Took {end - start} to send {messages_per_second} messages in thread {current_thread().getName()}")
            logger.debug(f"If greater than 0 seconds, sleeping for {sleep_time - (end - start)}")
            if sleep_time - (end - start) > 0:
                time.sleep(sleep_time - (end - start))