* Bạn có thể có các object **JSON lồng nhau** và tất cả chúng đã validate và annotated.
* **Có khả năng mở rộng**:
    * Pydantic cho phép bạn tùy chỉnh kiểu dữ liệu bằng việc định nghĩa hoặc bạn có thể mở rộng validation với các decorator trong model.

    * If you also declare dependencies in a specific *path operation*, **they will be executed too**.
    * The router dependencies are executed first, then the [`dependencies` in the decorator](dependencies/dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, and then the normal parameter dependencies.
    * You can also add [`Security` dependencies with `scopes`](../advanced/security/oauth2-scopes.md){.internal-link target=_blank}.

{!../../docs_src/first_steps/tutorial001.py!}
```
`@app.get("/")`は直下の関数が下記のリクエストの処理を担当することを**FastAPI**に伝えます:

* パス `/`
* <abbr title="an HTTP GET method"><code>get</code> オペレーション</abbr>

/// info | "`@decorator` について"

Pythonにおける`@something`シンタックスはデコレータと呼ばれます。

「デコレータ」は関数の上に置きます。かわいらしい装飾的な帽子のようです（この用語の由来はそこにあると思います）。

「デコレータ」は直下の関数を受け取り、それを使って何かを行います。

```Python
def get_settings():
    return Settings()
```

we would create that object for each request, and we would be reading the `.env` file for each request. ⚠️

But as we are using the `@lru_cache` decorator on top, the `Settings` object will be created only once, the first time it's called. ✔️

//// tab | Python 3.9+

```Python hl_lines="1  11"
{!> ../../docs_src/settings/app03_an_py39/main.py!}
```

////

import org.eclipse.aether.named.providers.NoopNamedLockFactory;
import org.eclipse.aether.spi.artifact.ArtifactPredicateFactory;
import org.eclipse.aether.spi.artifact.decorator.ArtifactDecoratorFactory;
import org.eclipse.aether.spi.artifact.generator.ArtifactGeneratorFactory;
import org.eclipse.aether.spi.checksums.ProvidedChecksumsSource;
import org.eclipse.aether.spi.checksums.TrustedChecksumsSource;

import org.eclipse.aether.named.providers.NoopNamedLockFactory;
import org.eclipse.aether.spi.artifact.ArtifactPredicateFactory;
import org.eclipse.aether.spi.artifact.decorator.ArtifactDecoratorFactory;
import org.eclipse.aether.spi.artifact.generator.ArtifactGeneratorFactory;
import org.eclipse.aether.spi.checksums.ProvidedChecksumsSource;
import org.eclipse.aether.spi.checksums.TrustedChecksumsSource;

In diesen Fällen können Sie, anstatt einen Parameter der *Pfadoperation-Funktion* mit `Depends` zu deklarieren, eine `list`e von `dependencies` zum *Pfadoperation-Dekorator* hinzufügen.

## `dependencies` zum *Pfadoperation-Dekorator* hinzufügen

Der *Pfadoperation-Dekorator* erhält ein optionales Argument `dependencies`.

Es sollte eine `list`e von `Depends()` sein:

//// tab | Python 3.9+

```Python hl_lines="19"

Para esses casos, em vez de declarar um parâmetro em uma *função de operação de rota* com `Depends`, você pode adicionar um argumento `dependencies` do tipo `list` ao decorador da operação de rota.

## Adicionando `dependencies` ao decorador da operação de rota

O *decorador da operação de rota* recebe um argumento opcional `dependencies`.

Ele deve ser uma lista de `Depends()`:

//// tab | Python 3.9+

```Python hl_lines="19"

* Fix PDB e2e test, off-by-one ([#35274](https://github.com/kubernetes/kubernetes/pull/35274), [@soltysh](https://github.com/soltysh))
* etcd3: API storage - decouple decorator from filter ([#31189](https://github.com/kubernetes/kubernetes/pull/31189), [@hongchaodeng](https://github.com/hongchaodeng))

        TF2 by enabling tracking of nested keras models created in TF1-style,
        when used with the `tf.compat.v1.keras.utils.track_tf1_style_variables`
        decorator.
    *   Added a `tf.keras.layers.experimental.preprocessing.HashedCrossing`
        layer which applies the hashing trick to the concatenation of crossed