from pydantic import BaseModel

app = FastAPI()


class BaseItem(BaseModel):
    description: str
    type: str


class CarItem(BaseItem):
    type: str = "car"


class PlaneItem(BaseItem):
    type: str = "plane"
    size: int


items = {
    "item1": {"description": "All my friends drive a low rider", "type": "car"},
    "item2": {

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}

### `Union` in Python 3.10 { #union-in-python-3-10 }

In this example we pass `Union[PlaneItem, CarItem]` as the value of the argument `response_model`.

                            }
                        ],
                    }
                }
            },
            "components": {
                "schemas": {
                    "PlaneItem": {
                        "title": "PlaneItem",
                        "required": ["description", "size"],
                        "type": "object",
                        "properties": {

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}


### `Union` en Python 3.10 { #union-in-python-3-10 }

En este ejemplo pasamos `Union[PlaneItem, CarItem]` como el valor del argumento `response_model`.

from pydantic import BaseModel

app = FastAPI()


class BaseItem(BaseModel):
    description: str
    type: str


class CarItem(BaseItem):
    type: str = "car"


class PlaneItem(BaseItem):
    type: str = "plane"
    size: int


items = {
    "item1": {"description": "All my friends drive a low rider", "type": "car"},
    "item2": {

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}

### `Union` in Python 3.10 { #union-in-python-3-10 }

In diesem Beispiel übergeben wir `Union[PlaneItem, CarItem]` als Wert des Arguments `response_model`.

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}

### `Union` в Python 3.10 { #union-in-python-3-10 }

В этом примере мы передаём `Union[PlaneItem, CarItem]` в качестве значения аргумента `response_model`.

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}

### `Union` no Python 3.10 { #union-in-python-3-10 }

Neste exemplo, passamos `Union[PlaneItem, CarItem]` como o valor do argumento `response_model`.

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}


### Python 3.10에서 `Union`

위의 예제에서는 `response_model` 인자 값으로 `Union[PlaneItem, CarItem]`을 전달합니다.

/// note | 笔记

定义 <a href="https://docs.pydantic.dev/latest/concepts/types/#unions" class="external-link" target="_blank">`Union`</a> 类型时，要把详细的类型写在前面，然后是不太详细的类型。下例中，更详细的 `PlaneItem` 位于 `Union[PlaneItem，CarItem]` 中的 `CarItem` 之前。

///

{* ../../docs_src/extra_models/tutorial003_py310.py hl[1,14:15,18:20,33] *}

## 模型列表

使用同样的方式也可以声明由对象列表构成的响应。

为此，请使用标准的 Python `typing.List`：