docs: @Override
  	public void setup(AbstractInvokable parent) {
  		@SuppressWarnings("unchecked")
  		final ReduceFunction<IT> red = BatchTask.instantiateUserCode(this.config, userCodeClassLoader, ReduceFunction.class);
  		this.reducer = red;
  		FunctionUtils.setFunctionRuntimeContext(red, getUdfRuntimeContext());
  
  		TypeSerializerFactory<IT> serializerFactory = this.config.getInputSerializer(0, userCodeClassLoader);
  		this.serializer = serializerFactory.getSerializer();
  
  		if (LOG.isDebugEnabled()) {
  			LOG.debug("ChainedAllReduceDriver object reuse: " + (this.objectReuseEnabled ? "ENABLED" : "DISABLED") + ".");
  		}
  	}