code: func CloneAndAddLabel(labels map[string]string, labelKey string, labelValue uint32) map[string]string {
  	if labelKey == "" {
  		// Dont need to add a label.
  		return labels
  	}
  	// Clone.
  	newLabels := map[string]string{}
  	for key, value := range labels {
  		newLabels[key] = value
  	}
  	newLabels[labelKey] = fmt.Sprintf("%d", labelValue)
  	return newLabels
  }
docs: // Clones the given map and returns a new map with the given key and value added.
  // Returns the given map, if labelKey is empty.