code: func (plugin *ExamplePlugin) Init() (err error) {
  	// Create a synchronous publisher.
  	// In the manual mode, every publisher has selected its target partition.
  	plugin.kafkaSyncPublisher, err = plugin.Kafka.NewSyncPublisherToPartition(connection, topic1, syncMessagePartition)
  	if err != nil {
  		return err
  	}
  
  	// Prepare subscription channel. Relevant kafka messages are send to this
  	// channel so that the watcher can read it.
  	plugin.subscription = make(chan messaging.ProtoMessage)
  
  	plugin.Log.Info("Initialization of the custom plugin for the Kafka example is completed")
  
  	// Run the producer.
  	go plugin.producer()
  
  	// Verify results and close the example if successful.
  	go plugin.closeExample()
  
  	return err
  }
docs: // Init initializes and starts producers