code: private SerFunction<?,?> determineUnmapFunction(String lastOperationName){
  		return Ops.classify.name().equals(lastOperationName) ? this.shuffleResultNormalizer : s -> s; 
  	}
docs: Determines which unmap function to use. For cases when previous operation was 'classify'
  the unmap function is {@link #unmapFunction} otherwise it will produce a pass thru function.