code: func NewNodeLabelPriority(label string, presence bool) (PriorityMapFunction, PriorityReduceFunction) {
  	labelPrioritizer := &NodeLabelPrioritizer{
  		label:    label,
  		presence: presence,
  	}
  	return labelPrioritizer.CalculateNodeLabelPriorityMap, nil
  }
docs: // NewNodeLabelPriority creates a NodeLabelPrioritizer.