```Python hl_lines="2  7-10 23-25"
from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool | None = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str | None = None):

多虧了 Pydantic，你可以用標準的 Python 型別來宣告 body。

```Python hl_lines="2  7-10 23-25"
from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool | None = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str | None = None):

# Prise en charge des éditeurs { #editor-support }

L’extension officielle [Extension FastAPI](https://marketplace.visualstudio.com/items?itemName=FastAPILabs.fastapi-vscode) améliore votre flux de développement FastAPI grâce à la découverte des chemins d'accès, à la navigation, ainsi qu’au déploiement sur FastAPI Cloud et à la diffusion en direct des journaux.

Cela vous permet de **réutiliser le modèle** à **plusieurs endroits** et aussi de déclarer des validations et des métadonnées pour tous les paramètres en une seule fois. 😎

/// note | Remarque

Cela est pris en charge depuis la version `0.115.0` de FastAPI. 🤓

///

## Paramètres d'en-tête avec un modèle Pydantic { #header-parameters-with-a-pydantic-model }

<img src="/img/tutorial/generate-clients/image02.png">

Ayrıca gönderilecek payload için de otomatik tamamlama alırsınız:

<img src="/img/tutorial/generate-clients/image03.png">

/// tip | İpucu

`name` ve `price` için otomatik tamamlamaya dikkat edin; bunlar FastAPI uygulamasında, `Item` modelinde tanımlanmıştı.

///

Gönderdiğiniz veriler için satır içi hatalar (inline errors) da alırsınız:

例如，上述模型声明如下 JSON "object"（即 Python `dict`）：

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

...由于 `description` 和 `tax` 是可选的（默认值为 `None`），下面的 JSON "object" 也有效：

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

## 声明为参数 { #declare-it-as-a-parameter }

使用与声明路径和查询参数相同的方式，把它添加至*路径操作*：

     */
    private static final long DISTINCT_VALUES = 210;
    /**
     * The number of buckets to create in the {@link #multiBucket} case.
     * <p>
     * If this is not relatively prime to {@link #DISTINCT_VALUES_IN_BUCKETS}
     * then the values won't be scattered evenly across the buckets.
     */
    private static final long DISTINCT_BUCKETS = 21;
    /**

    bimap.putAll(map);
    return bimap;
  }

  private EnumHashBiMap(Class<K> keyType) {
    super(new EnumMap<K, V>(keyType), new HashMap<V, K>());
    // TODO: cpovirk - Pre-size the HashMap based on the number of enum values?
    this.keyTypeOrObjectUnderJ2cl = keyType;
  }

  // Overriding these 3 methods to show that values may be null (but not keys)

  @Override
  K checkKey(K key) {

        // replaces?
        AbstractRepositoryMetadata repoMetadata = (AbstractRepositoryMetadata) metadata;
        this.metadata.merge(repoMetadata.getMetadata());
    }

    @Override
    public void merge(ArtifactMetadata metadata) {
        // TODO not sure that it should assume this, maybe the calls to addMetadata should pre-merge, then artifact
        // replaces?

 * <p>
 * Consider the following output of <code>examples/SidLookup.java</code>:
 *
 * <pre>
 *        toString: S-1-5-21-4133388617-793952518-2001621813-512
 * toDisplayString: WNET\Domain Admins
 *         getType: 2
 *     getTypeText: Domain group
 *   getDomainName: WNET
 *  getAccountName: Domain Admins
 * </pre>
 */
public interface SID {

    /**
     * SID type indicating no type information.
     */