private void readObject(ObjectInputStream stream) throws InvalidObjectException {
    throw new InvalidObjectException("Use SerializedForm");
  }

  /*
   * This class is used to serialize ImmutableEnumSet instances.
   */
  @J2ktIncompatible // serialization
  private static final class EnumSerializedForm<E extends Enum<E>> implements Serializable {
    final EnumSet<E> delegate;

        StringWriter writer = new StringWriter(1024 * 4);

        try {
            settingsWriter.write(writer, null, settings);
        } catch (IOException e) {
            throw new IllegalStateException("Failed to serialize settings to memory", e);
        }

        String serializedSettings = writer.toString();

        RegexBasedInterpolator interpolator = new RegexBasedInterpolator();

    /**
     * @throws Exception
     */
    public void testSerialize() throws Exception {
        final String[] a = new String[] { "1", "2" };
        final String[] b = (String[]) SerializeUtil.serialize(a);
        assertEquals("1", b.length, a.length);
        assertEquals("2", "1", b[0]);
        assertEquals("3", "2", b[1]);
    }

    /**
     * @throws Exception
     */

```

</div>

Then go to the `/docs` UI, you will see that **FastAPI** is using these **models** to **document** the API, and it will use them to **serialize** and **validate** the data too.

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

## Update the App with Multiple Models { #update-the-app-with-multiple-models }

            raise ResponseValidationError(
                errors=errors,
                body=response_content,
                endpoint_ctx=ctx,
            )

        return field.serialize(
            value,
            include=include,
            exclude=exclude,
            by_alias=by_alias,
            exclude_unset=exclude_unset,
            exclude_defaults=exclude_defaults,

	log.SetPrefix("go_android_exec: ")
	exitCode, err := runMain()
	if err != nil {
		log.Fatal(err)
	}
	os.Exit(exitCode)
}

func runMain() (int, error) {
	// Concurrent use of adb is flaky, so serialize adb commands.
	// See https://github.com/golang/go/issues/23795 or
	// https://issuetracker.google.com/issues/73230216.
	lockPath := filepath.Join(os.TempDir(), "go_android_exec-adb-lock")

import org.jspecify.annotations.Nullable;

/**
 * Provides static methods for serializing collection classes.
 *
 * <p>This class assists the implementation of collection classes. Do not use this class to
 * serialize collections that are defined elsewhere.
 *
 * @author Jared Levy
 */
@GwtIncompatible
@J2ktIncompatible
final class Serialization {
  private Serialization() {}

  /**

     * @throws Exception
     */
    @Test
    public void testSerialize() throws Exception {
        list.addLast("1");
        list.addLast("2");
        list.addLast("3");
        assertThat(SerializeUtil.serialize(list), is(notNullValue()));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testSet() throws Exception {
        list.addLast("1");
        list.addLast("2");

    assertEquals(Integer.valueOf(5), reserialize(Suppliers.ofInstance(5)).get());
    assertEquals(
        Integer.valueOf(5),
        reserialize(Suppliers.compose(Functions.identity(), Suppliers.ofInstance(5))).get());
    assertEquals(Integer.valueOf(5), reserialize(Suppliers.memoize(Suppliers.ofInstance(5))).get());
    assertEquals(
        Integer.valueOf(5),

    assertEquals(Integer.valueOf(5), reserialize(Suppliers.ofInstance(5)).get());
    assertEquals(
        Integer.valueOf(5),
        reserialize(Suppliers.compose(Functions.identity(), Suppliers.ofInstance(5))).get());
    assertEquals(Integer.valueOf(5), reserialize(Suppliers.memoize(Suppliers.ofInstance(5))).get());
    assertEquals(
        Integer.valueOf(5),