),
                        "price": {"title": "Price", "type": "number"},
                        "tax": IsDict(
                            {
                                "title": "Tax",
                                "anyOf": [{"type": "number"}, {"type": "null"}],
                            }
                        )
                        | IsDict(

                        ),
                        "price": {"title": "Price", "type": "number"},
                        "tax": IsDict(
                            {
                                "title": "Tax",
                                "anyOf": [{"type": "number"}, {"type": "null"}],
                            }
                        )
                        | IsDict(

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

↩️:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## 🌃

👆 💪 🚮 💗 💪 🔢 👆 *➡ 🛠️ 🔢*, ✋️ 📨 💪 🕴 ✔️ 👁 💪.

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

以下の代わりに:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## まとめ

リクエストが単一のボディしか持てない場合でも、*path operation関数*に複数のボディパラメータを追加することができます。

                        ),
                        "price": {"title": "Price", "type": "number"},
                        "tax": IsDict(
                            {
                                "title": "Tax",
                                "anyOf": [{"type": "number"}, {"type": "null"}],
                            }
                        )
                        | IsDict(

```JSON hl_lines="2"
{
    "item": {
        "name": "Foo",
        "description": "The pretender",
        "price": 42.0,
        "tax": 3.2
    }
}
```

instead of:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2
}
```

## Recap

    "price": 62,
    "tax": 20.2
}
```

they will be included in the response.

#### Data with the same values as the defaults

If the data has the same values as the default ones, like the item with ID `baz`:

```Python hl_lines="3  5-6"
{
    "name": "Baz",
    "description": None,
    "price": 50.2,
    "tax": 10.5,
    "tags": []
}
```

예를 들면, 위의 이 모델은 JSON "`object`" (혹은 파이썬 `dict`)을 다음과 같이 선언합니다:

```JSON
{
    "name": "Foo",
    "description": "선택적인 설명란",
    "price": 45.2,
    "tax": 3.5
}
```

...`description`과 `tax`는 (기본 값이 `None`으로 되어 있어) 선택적이기 때문에, 이 JSON "`object`"는 다음과 같은 상황에서도 유효합니다:

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

## 매개변수로서 선언하기

from fastapi import FastAPI
from pydantic import BaseModel


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


app = FastAPI()


@app.post("/items/")
async def create_item(item: Item):

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: list = []


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):
    results = {"item_id": item_id, "item": item}