return metrics
	})
	return mg
}

// getHistogramMetrics fetches histogram metrics and returns it in a []Metric
// Note: Typically used in MetricGroup.RegisterRead
//
// The toLowerAPILabels parameter is added for compatibility,
// if set, it lowercases the `api` label values.
func getHistogramMetrics(hist *prometheus.HistogramVec, desc MetricDescription, toLowerAPILabels, limitBuckets bool) []MetricV2 {

  public static <C extends @Nullable Object, K extends C, V extends @Nullable Object>
      TreeMap<K, V> newTreeMap(@Nullable Comparator<C> comparator) {
    // Ideally, the extra type parameter "C" shouldn't be necessary. It is a
    // work-around of a compiler type inference quirk that prevents the
    // following code from being compiled:
    // Comparator<Class<?>> comparator = null;

  public static <C extends @Nullable Object, K extends C, V extends @Nullable Object>
      TreeMap<K, V> newTreeMap(@Nullable Comparator<C> comparator) {
    // Ideally, the extra type parameter "C" shouldn't be necessary. It is a
    // work-around of a compiler type inference quirk that prevents the
    // following code from being compiled:
    // Comparator<Class<?>> comparator = null;