*
 * `numerical_grad` is the pointer to the AbstractTensorHandle* which will
 * hold the numerical gradient data at the end of the function.
 */
absl::Status CalcNumericalGrad(AbstractContext* ctx, Model forward,
                               absl::Span<AbstractTensorHandle* const> inputs,
                               int input_index, bool use_function,
                               AbstractTensorHandle** numerical_grad);

// A goroutine will be started and run until the provided context is canceled.
func (r *RingBuffer) WithCancel(ctx context.Context) *RingBuffer {
	go func() {
		select {
		case <-ctx.Done():
			r.CloseWithError(ctx.Err())
		}
	}()
	return r
}

func (r *RingBuffer) setErr(err error, locked bool) error {
	if !locked {
		r.mu.Lock()
		defer r.mu.Unlock()
	}

		"Total number of messages sent to this target",
		allWebhookLabels...)
)

// loadLoggerWebhookMetrics - `MetricsLoaderFn` for logger webhook
// such as failed messages and total messages.
func loadLoggerWebhookMetrics(ctx context.Context, m MetricValues, c *metricsCache) error {
	tgts := append(logger.SystemTargets(), logger.AuditTargets()...)
	for _, t := range tgts {
		labels := []string{nameL, t.String(), endpointL, t.Endpoint()}

)

func b2f(v bool) float64 {
	if v {
		return 1
	}
	return 0
}

// loadClusterErasureSetMetrics - `MetricsLoaderFn` for cluster storage erasure
// set metrics.
func loadClusterErasureSetMetrics(ctx context.Context, m MetricValues, c *metricsCache) error {
	result, _ := c.esetHealthResult.Get()

	m.Set(erasureSetOverallWriteQuorum, float64(result.WriteQuorum))
	m.Set(erasureSetOverallHealth, b2f(result.Healthy))

		size += len(block)
	}
	return size
}

// Writes all the data blocks from encoded blocks until requested
// outSize length. Provides a way to skip bytes until the offset.
func writeDataBlocks(ctx context.Context, dst io.Writer, enBlocks [][]byte, dataBlocks int, offset int64, length int64) (int64, error) {
	// Offset and out size cannot be negative.
	if offset < 0 || length < 0 {
		return 0, errUnexpected
	}

		},
		rcfg:         replicationConfig{Config: &configs[0]},
		expectedSync: false,
	},
}

func TestReplicationResync(t *testing.T) {
	ctx := context.Background()
	for i, test := range replicationConfigTests {
		if sync := test.rcfg.Resync(ctx, test.info, test.dsc, test.tgtStatuses); sync.mustResync() != test.expectedSync {

		fmt.Println(err)
		return
	}

	scopes := ddoc.ScopesSupported
	if clientScopes != "" {
		scopes = strings.Split(clientScopes, ",")
	}

	ctx := context.Background()

	config := oauth2.Config{
		ClientID:     clientID,
		ClientSecret: clientSec,
		Endpoint: oauth2.Endpoint{
			AuthURL:  ddoc.AuthEndpoint,
			TokenURL: ddoc.TokenEndpoint,
		},

)

// loadClusterReplicationMetrics - `MetricsLoaderFn` for cluster replication metrics
// such as transfer rate and objects queued.
func loadClusterReplicationMetrics(ctx context.Context, m MetricValues, c *metricsCache) error {
	st := globalReplicationStats.Load()
	if st == nil {
		return nil
	}

	qs := st.getNodeQueueStatsSummary()

	qt := qs.QStats

	bodyDoneCh := make(chan struct{})
	doneCh := make(chan error)
	ctx := r.Context()
	go func() {
		canWrite := true
		write := func(b []byte) {
			if canWrite {
				n, err := w.Write(b)
				if err != nil || n != len(b) {
					canWrite = false
				}
			}
		}
		// Wait for body to be read.
		select {
		case <-ctx.Done():
		case <-bodyDoneCh:
		case err := <-doneCh:
			if err != nil {

	} else {
		cfg.inlineBlock = 128 * humanize.KiByte
	}

	cfg.initialized = true

	return cfg, nil
}

func configLogOnceIf(ctx context.Context, err error, id string, errKind ...interface{}) {
	logger.LogOnceIf(ctx, "config", err, id, errKind...)