from typing import Optional, Union

from fastapi import FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: Optional[str] = None


class ExtendedItem(Item):
    age: int


@app.post("/items/")
def save_union_different_body(item: Union[ExtendedItem, Item]):
    return {"item": item}


client = TestClient(app)

from pydantic import BaseModel

app = FastAPI()


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


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


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


@app.put("/items/{item_id}")

## Classes as dependencies { #classes-as-dependencies_1 }

You might notice that to create an instance of a Python class, you use that same syntax.

For example:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

In this case, `fluffy` is an instance of the class `Cat`.

And to create `fluffy`, you are "calling" `Cat`.

Você deve ter percebido que para criar um instância de uma classe em Python, a mesma sintaxe é utilizada.

Por exemplo:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

Nesse caso,  `fluffy` é uma instância da classe `Cat`.

E para criar `fluffy`, você está "chamando" `Cat`.

			}
		}

		str := getUserAgent(testCase.mode)
		expectedStr := testCase.expectedStr
		if IsDocker() {
			expectedStr = strings.ReplaceAll(expectedStr, "; source", "; docker; source")
		}
		if !strings.Contains(str, expectedStr) {
			t.Errorf("Test %d: expected: %s, got: %s", i+1, expectedStr, str)
		}
		os.Unsetenv("MARATHON_APP_LABEL_DCOS_PACKAGE_VERSION")

    ],
)
def get_mod_path(request: pytest.FixtureRequest):
    mod_path = f"docs_src.settings.{request.param}"
    return mod_path


@pytest.fixture(name="main_mod")
def get_main_mod(mod_path: str) -> ModuleType:
    main_mod = importlib.import_module(f"{mod_path}.main")
    return main_mod


def test_settings(main_mod: ModuleType, monkeypatch: MonkeyPatch):
    monkeypatch.setenv("ADMIN_EMAIL", "******@****.***")

    return mod.html


@pytest.fixture(name="client")
def get_client(mod: ModuleType):
    client = TestClient(mod.app)

    return client


def test_get(client: TestClient, html: str):
    response = client.get("/")
    assert response.text == html


def test_websocket_handle_disconnection(client: TestClient):
    with (
        client.websocket_connect("/ws/1234") as connection,

```Python hl_lines="1"
async def needy_dependency(fresh_value: Annotated[str, Depends(get_value, use_cache=False)]):
    return {"fresh_value": fresh_value}
```

////

//// tab | Python 3.9+ без Annotated

/// tip | Подсказка

Предпочтительнее использовать версию с аннотацией, если это возможно.

///

```Python hl_lines="1"
async def needy_dependency(fresh_value: str = Depends(get_value, use_cache=False)):

{* ../../docs_src/query_params/tutorial005_py39.py hl[6:7] *}

Here the query parameter `needy` is a required query parameter of type `str`.

If you open in your browser a URL like:

```
http://127.0.0.1:8000/items/foo-item
```

...without adding the required parameter `needy`, you will see an error like:

```JSON
{

更新数据请用 <a href="https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Methods/PUT" class="external-link" target="_blank">HTTP `PUT`</a> 操作。

把输入数据转换为以 JSON 格式存储的数据（比如，使用 NoSQL 数据库时），可以使用 `jsonable_encoder`。例如，把 `datetime` 转换为 `str`。

{* ../../docs_src/body_updates/tutorial001.py hl[30:35] *}

`PUT` 用于接收替换现有数据的数据。

### 关于更新数据的警告

用 `PUT` 把数据项 `bar` 更新为以下内容时：

```Python
{
    "name": "Barz",
    "price": 3,