* Editor support, including:
    * Completion.
    * Type checks.
* Validation of data:
    * Automatic and clear errors when the data is invalid.
    * Validation even for deeply nested JSON objects.
* <dfn title="also known as: serialization, parsing, marshalling">Conversion</dfn> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.

```

</div>

/// note | Not

`uvicorn main:app` komutu şunları ifade eder:

* `main`: `main.py` dosyası (Python "module").
* `app`: `main.py` içinde `app = FastAPI()` satırıyla oluşturulan nesne.

Şununla eşdeğerdir:

```Python
from main import app
```

///

Her alternatif ASGI server programı için benzer bir komut bulunur; daha fazlası için ilgili dokümantasyonlarına bakabilirsiniz.

    }

    @Test
    public void test_longComponentName() {
        // Test with a very long component name
        String longName = "com.example.very.long.package.name.with.many.nested.levels.MyVeryLongComponentNameThatExceedsNormalLength";
        ContainerNotAvailableException exception = new ContainerNotAvailableException(longName, null);

    assertThat(getClass().getResource("internal/Finalizer.class")).isNotNull();
  }

  @Test
  public void testFinalizeClassHasNoNestedClasses() throws Exception {
    // Ensure that the Finalizer class has no nested classes.
    // See https://github.com/google/guava/issues/1505
    assertThat(Finalizer.class.getDeclaredClasses()).isEmpty();
  }

  static class MyServerExampleWithFrq implements Closeable {

## Model Listesi { #list-of-models }

Aynı şekilde, nesne listesi döndüren response'ları da tanımlayabilirsiniz.

Bunun için standart Python `list`'i kullanın:

{* ../../docs_src/extra_models/tutorial004_py310.py hl[18] *}

  public void testLenientFormat_badArgumentToString() {
    assertThat(Strings.lenientFormat("boiler %s plate", new ThrowsOnToString()))
        .matches(
            // J2kt nested class name does not use "$"
            "boiler <com\\.google\\.common\\.base\\.StringsTest[.$]ThrowsOnToString@[0-9a-f]+ "
                + "threw java\\.lang\\.UnsupportedOperationException> plate");
  }

dataclass は自動的に Pydantic の dataclass に変換されます。

このため、そのスキーマは API ドキュメントの UI に表示されます:

<img src="/img/tutorial/dataclasses/image01.png">

## ネストしたデータ構造での dataclasses { #dataclasses-in-nested-data-structures }

`dataclasses` を他の型注釈と組み合わせて、ネストしたデータ構造を作成できます。

場合によっては、自動生成された API ドキュメントでエラーが発生するなどの理由で、Pydantic 版の `dataclasses` を使う必要があるかもしれません。

Você também poderá receber verificações de erros para operações de tipos incorretas:

<img src="/img/tutorial/body/image04.png">

Isso não é por acaso, todo o framework foi construído em volta deste design.

E foi imensamente testado na fase de design, antes de qualquer implementação, para garantir que funcionaria para todos os editores de texto.

Houveram mudanças no próprio Pydantic para que isso fosse possível.

Vous pouvez également utiliser les paramètres du *décorateur de chemin d'accès* `response_model_include` et `response_model_exclude`.

Ils prennent un `set` de `str` avec les noms des attributs à inclure (en omettant le reste) ou à exclure (en incluant le reste).

Cela peut être utilisé comme un raccourci rapide si vous n'avez qu'un seul modèle Pydantic et que vous souhaitez supprimer certaines données de la sortie.

/// tip | Astuce

        StackTraceElement topElement = stackTrace[0];
        assertEquals(this.getClass().getName(), topElement.getClassName());
    }

    @Test
    public void test_nestedExceptions() {
        // Test nested exception handling
        Exception level3 = new RuntimeException("Level 3 error");
        Exception level2 = new IllegalStateException("Level 2 error", level3);