return prometheus.NewDesc(
		md.toPromName(namePrefix),
		md.Help,
		md.VariableLabels, extraLabels,
	)
}

// NewCounterMD - creates a new counter metric descriptor.
func NewCounterMD(name MetricName, help string, labels ...string) MetricDescriptor {
	return MetricDescriptor{
		Name:           name,
		Type:           CounterMT,
		Help:           help,