6. Aqui estamos retornando um dicionário que contém `items`, que é uma lista de dataclasses.

    O FastAPI ainda é capaz de <abbr title="converter os dados para um formato que pode ser transmitido">serializar</abbr> os dados para JSON.

7. Aqui o `response_model` está usando uma anotação de tipo de uma lista de dataclasses `Author`.

    Novamente, você pode combinar `dataclasses` com anotações de tipo padrão.

```

</div>

Então, vá para a interface `/docs`, você verá que o **FastAPI** está usando esses **modelos** para **documentar** a API, e ele também os usará para **serializar** e **validar** os dados.

<div class="screenshot">
<img src="/img/tutorial/sql-databases/image01.png">
</div>

## Atualizar o App com Múltiplos Modelos

var serializerMap = sync.Map{}

// RegisterSerializer register serializer
func RegisterSerializer(name string, serializer SerializerInterface) {
	serializerMap.Store(strings.ToLower(name), serializer)
}

// GetSerializer get serializer
func GetSerializer(name string) (serializer SerializerInterface, ok bool) {
	v, ok := serializerMap.Load(strings.ToLower(name))
	if ok {
		serializer, ok = v.(SerializerInterface)
	}
	return serializer, ok
}

* Existing usages of Serializer outside of this infrastructure should be migrated to use it.
* Existing usages of Java serialization should be migrated to use it.
* It is ok for Serializer to be used as a replacement for Java serialization as a migration step.

     * be created automatically.
     *
     * @param output The file to serialize the settings to, must not be {@code null}.
     * @param options The options to use for serialization, may be {@code null} to use the default values.
     * @param settings The settings to serialize, must not be {@code null}.
     * @throws IOException If the settings could not be serialized.
     */

     * created automatically.
     *
     * @param output The file to serialize the model to, must not be {@code null}.
     * @param options The options to use for serialization, may be {@code null} to use the default values.
     * @param model The model to serialize, must not be {@code null}.
     * @throws IOException If the model could not be serialized.
     */

final class SingletonImmutableList<E> extends ForwardingImmutableList<E> {

  final transient List<E> delegate;
  // This reference is used both by the custom field serializer, and by the
  // GWT compiler to infer the elements of the lists that needs to be
  // serialized.
  E element;

  SingletonImmutableList(E element) {
    this.delegate = singletonList(checkNotNull(element));
    this.element = element;
  }

  @Override

     * the method returns.
     *
     * @param output The writer to serialize the toolchains to, must not be {@code null}.
     * @param options The options to use for serialization, may be {@code null} to use the default values.
     * @param toolchains The toolchains to serialize, must not be {@code null}.
     * @throws IOException If the toolchains could not be serialized.
     */

// 	{
// 		"kind":"MyAPIObject",
// 		"apiVersion":"v1",
// 		"myPlugin": {
// 			"kind":"PluginA",
// 			"aOption":"foo",
// 		},
// 	}
//
// So what happens? Decode first uses json or yaml to unmarshal the serialized data into
// your external MyAPIObject. That causes the raw JSON to be stored, but not unpacked.
// The next step is to copy (using pkg/conversion) into the internal struct. The runtime

		if err != nil {
			return keys, err
		}
	}
	return keys, nil
}

// serialize will serialize the provided keys and values.
// The function will panic if keys/value slices aren't of equal length.
// Payload size can give an indication of expected payload size.
// If plSize is <= 0 it will be calculated.
func (x *xlMetaInlineData) serialize(plSize int, keys [][]byte, vals [][]byte) {
	if len(keys) != len(vals) {