// AnnotationTopologyMode can be used to enable or disable Topology Aware
	// Routing for a Service. Well known values are "Auto" and "Disabled".
	// Implementations may choose to develop new topology approaches, exposing
	// them with domain-prefixed values. For example, "example.com/lowest-rtt"
	// could be a valid implementation-specific value for this annotation. These

image::performance/build-scan-performance-page.png[title="Build scan performance page"]

In the above build scan, configuration takes over 13 seconds.
Click on the _"Configuration"_ tab to break this stage into component parts,
exposing the cause of the slowness.

image::performance/build-scan-configuration-breakdown.png[title="Build scan configuration breakdown"]

	"k8s.io/apimachinery/pkg/util/validation"
	apiservercel "k8s.io/apiserver/pkg/cel"
	"k8s.io/kube-openapi/pkg/validation/strfmt"
)

// Format provides a CEL library exposing common named Kubernetes string
// validations. Can be used in CRD ValidationRules messageExpression.
//
//  Example:
//
//    rule:              format.dns1123label.validate(object.metadata.name).hasValue()

// an equivalent structural schema instance.
//
// This lets us avoid needing a separate adaptor for the nested value
// validations, and doesn't cost too much since since we are usually exploring the
// entire schema anyway.
func nestedValueValidationToStructural(nvv *schema.NestedValueValidation) *Structural {
	var newItems *schema.Structural
	if nvv.Items != nil {

		KubeletFlags:         *hk.KubeletFlags,
		KubeletConfiguration: *hk.KubeletConfiguration,
	}, hk.KubeletDeps, false); err != nil {
		klog.Fatalf("Failed to run HollowKubelet: %v. Exiting.", err)
	}
	select {}
}

// HollowKubeletOptions contains settable parameters for hollow kubelet.
type HollowKubeletOptions struct {
	NodeName            string
	KubeletPort         int

	// Extract the output string.
	return outBuffer.String(), err
}

func processHTTPResponse(requestID int, httpResp *http.Response, outBuffer *bytes.Buffer) error {
	// Make sure we close the body before exiting.
	defer func() {
		if err := httpResp.Body.Close(); err != nil {
			echo.WriteError(outBuffer, requestID, err)
		}
	}()

	// AnnotationTopologyMode can be used to enable or disable Topology Aware
	// Routing for a Service. Well known values are "Auto" and "Disabled".
	// Implementations may choose to develop new topology approaches, exposing
	// them with domain-prefixed values. For example, "example.com/lowest-rtt"
	// could be a valid implementation-specific value for this annotation. These

	if features.EnableMCSServiceDiscovery {
		// MCS spec does not allow export of external name services.
		// See https://github.com/kubernetes/enhancements/tree/master/keps/sig-multicluster/1645-multi-cluster-services-api#exporting-services.
		discoverabilityPolicy = model.DiscoverableFromSameCluster
	}
	for _, portEntry := range svc.Ports {
		out = append(out, &model.IstioEndpoint{
			Address:               svc.Attributes.ExternalName,

    await do_stuff()
```

When you create a context manager or an async context manager like above, what it does is that, before entering the `with` block, it will execute the code before the `yield`, and after exiting the `with` block, it will execute the code after the `yield`.

In our code example above, we don't use it directly, but we pass it to FastAPI for it to use it.

// formerly blocked in c starts running.
// These switches continue until a call to coroexit(c),
// which ends the use of the coro by releasing the blocked
// goroutine in c and exiting the current goroutine.
//
// Coros are heap allocated and garbage collected, so that user code
// can hold a pointer to a coro without causing potential dangling
// pointer errors.
type coro struct {
	gp guintptr