go.opentelemetry.io/otel/api/metric.BatchObserverMust.NewFloat64UpDownSumObserver (method)

one use

	go.opentelemetry.io/otel/api/metric (current package)
		must.go#L216: func (bm BatchObserverMust) NewFloat64UpDownSumObserver(name string, oos ...InstrumentOption) Float64UpDownSumObserver {