**FastAPI**は<a href="https://docs.pydantic.dev/" class="external-link" target="_blank"><strong>Pydantic </strong></a>と完全に互換性があります（そしてベースになっています）。したがって、追加のPydanticコードがあれば、それも機能します。

データベースのために<abbr title = "Object-Relational Mapper">ORM</abbr>sや、<abbr title = "Object-Document Mapper">ODM</abbr>sなどの、Pydanticに基づく外部ライブラリを備えています。

これは、すべてが自動的に検証されるため、多くの場合、リクエストから取得したオブジェクトを**データベースに直接**渡すことができるということを意味しています。

同じことがその逆にも当てはまり、多くの場合、データベースから取得したオブジェクトを**クライアントに直接**渡すことができます。

```Python
q: str | None = None
```

////

//// tab | Python 3.9+

```Python
q: Union[str, None] = None
```

////

Was wir tun werden, ist, dies mit `Annotated` zu wrappen, sodass es zu:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.9+

```Python
q: Annotated[Union[str, None]] = None
```

////

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Test suites for wrappers in {@code Maps}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
@AndroidIncompatible // test-suite builders
public class MapsCollectionTest extends TestCase {
  public static Test suite() {

En déclarant les types de vos variables, cela permet aux différents outils comme les éditeurs de texte d'offrir un meilleur support.

Ce chapitre n'est qu'un **tutoriel rapide / rappel** sur les annotations de type Python.
Seulement le minimum nécessaire pour les utiliser avec **FastAPI** sera couvert... ce qui est en réalité très peu.

pkg syscall (freebsd-386), const TCP_VENDOR ideal-int
pkg syscall (freebsd-386), const WEXITED = 16
pkg syscall (freebsd-386), const WEXITED ideal-int
pkg syscall (freebsd-386), const WTRAPPED = 32
pkg syscall (freebsd-386), const WTRAPPED ideal-int
pkg syscall (freebsd-386), func Accept4(int, int) (int, Sockaddr, error)
pkg syscall (freebsd-386), func FcntlFlock(uintptr, int, *Flock_t) error

      boolean completedWithFailure = setException(throwable);
      if (!completedWithFailure) {
        // Go up the causal chain to see if we've already seen this cause; if we have, even if
        // it's wrapped by a different exception, don't log it.
        boolean firstTimeSeeingThisException = addCausalChain(getOrInitSeenExceptions(), throwable);
        if (firstTimeSeeingThisException) {
          log(throwable);

 *       collection. This is a stronger guarantee than that of {@link
 *       Collections#unmodifiableCollection}, whose contents change whenever the wrapped collection
 *       is modified.
 *   <li><b>Null-hostility.</b> This collection will never contain a null element.
 *   <li><b>Deterministic iteration.</b> The iteration order is always well-defined, depending on

    assertThat(callCount.get()).isEqualTo(2);
  }

  /**
   * On a concurrent computation that throws an unchecked exception, all threads should get the
   * (wrapped) exception, with the loader called only once. The result should not be cached (a later
   * request should call the loader again).
   */

Example:

    Source (English):

        «««
        <abbr title="Object Relational Mapper: a fancy term for a library where some classes represent SQL tables and instances represent rows in those tables">ORM</abbr>
        »»»

    Result (German):

        «««

   *
   * <p>Failure to follow this advice may result in non-deterministic behavior.
   *
   * <p>The returned table will be serializable if the specified table is serializable.
   *
   * @param table the table to be wrapped in a synchronized view
   * @return a synchronized view of the specified table
   * @since 22.0
   */
  @J2ktIncompatible // Synchronized