## Nested Models

Each attribute of a Pydantic model has a type.

But that type can itself be another Pydantic model.

So, you can declare deeply nested JSON "objects" with specific attribute names, types and validations.

All that, arbitrarily nested.

### Define a submodel

For example, we can define an `Image` model:

//// tab | Python 3.10+

```Python hl_lines="7-9"

 *
 *  2. If there is a connection in the pool that can satisfy the request it is used. Note that it is
 *     possible for shared exchanges to make requests to different host names! See
 *     [RealConnection.isEligible] for details.
 *
 *  3. Attempt plans from prior connect attempts for this call. These occur as either follow-ups to

///

## Shortcut to remember the names

Let's see the previous example again:

{* ../../docs_src/response_status_code/tutorial001.py hl[6] *}

`201` is the status code for "Created".

But you don't have to memorize what each of these codes mean.

			root.Scope.Debugf("Config file %q", root.IstioConfig)
			return runList(c.OutOrStdout())
		},
	}
	return listCmd
}

func runList(writer io.Writer) error {
	// Sort flag names
	keys := make([]string, len(settableFlags))
	i := 0
	for key := range settableFlags {
		keys[i] = key
		i++
	}
	sort.Strings(keys)
	w := new(tabwriter.Writer).Init(writer, 0, 8, 5, ' ', 0)

[pkg/validate/validate.go](pkg/validate/validate.go). These rules
refer to the Go struct path schema and hence have names with a capitalized first letter.
The Helm values.yaml API is validated in
[validate_values.go](pkg/validate/validate_values.go)
and refer to the values.yaml data paths. Hence, these rules have names with a lower case first letter.

  // Resources is a list of resources this rule applies to. '*' represents all resources.
  // +optional
  repeated string resources = 4;

  // ResourceNames is an optional white list of names that the rule applies to.  An empty set means that everything is allowed.
  // +optional
  repeated string resourceNames = 5;

## Documenting webhooks with **FastAPI** and OpenAPI

With **FastAPI**, using OpenAPI, you can define the names of these webhooks, the types of HTTP operations that your app can send (e.g. `POST`, `PUT`, etc.) and the request **bodies** that your app would send.

   */
  var typeHint: Any?
    get() = typeHintStack.lastOrNull()
    set(value) {
      typeHintStack[typeHintStack.size - 1] = value
    }

  /** Names leading to the current location in the ASN.1 document. */
  private val path = mutableListOf<String>()

  /**
   * False unless we made a recursive call to [write] at the current stack frame. The explicit box

 *
 * @author Kurt Alfred Kluever
 */
public class HttpHeadersTest extends TestCase {

  public void testConstantNameMatchesString() throws Exception {
    // Special case some of the weird HTTP Header names...
    ImmutableBiMap<String, String> specialCases =
        ImmutableBiMap.<String, String>builder()
            .put("CDN_LOOP", "CDN-Loop")
            .put("ETAG", "ETag")
            .put("SOURCE_MAP", "SourceMap")

 *
 * @author Kurt Alfred Kluever
 */
public class HttpHeadersTest extends TestCase {

  public void testConstantNameMatchesString() throws Exception {
    // Special case some of the weird HTTP Header names...
    ImmutableBiMap<String, String> specialCases =
        ImmutableBiMap.<String, String>builder()
            .put("CDN_LOOP", "CDN-Loop")
            .put("ETAG", "ETag")
            .put("SOURCE_MAP", "SourceMap")