name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item,
    user: User,
    importance: Annotated[int, Body(gt=0)],
    q: str | None = None,
):

from pydantic import BaseModel, Field

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = Field(
        default=None, title="The description of the item", max_length=300
    )
    price: float = Field(gt=0, description="The price must be greater than zero")
    tax: float | None = None


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

}


class Token(BaseModel):
    access_token: str
    token_type: str


class TokenData(BaseModel):
    username: str | None = None


class User(BaseModel):
    username: str
    email: str | None = None
    full_name: str | None = None
    disabled: bool | None = None


class UserInDB(User):
    hashed_password: str


password_hash = PasswordHash.recommended()

        "required": ["p"],
        "title": body_model_name,
        "type": "object",
    }


@pytest.mark.parametrize("json", [None, {}])
@pytest.mark.parametrize(
    "path",
    ["/required-str", "/model-required-str"],
)
def test_required_str_missing(path: str, json: dict[str, Any] | None):
    client = TestClient(app)
    response = client.post(path, json=json)
    assert response.status_code == 422

async def router_decorator_depends():
    return {"in": "router-decorator-depends"}


app.include_router(router)

client = TestClient(app)


async def overrider_dependency_simple(q: str | None = None):
    return {"q": q, "skip": 5, "limit": 10}


async def overrider_sub_dependency(k: str):
    return {"k": k}


async def overrider_dependency_with_sub(msg: dict = Depends(overrider_sub_dependency)):

        assertFalse(cos.done);
        assertTrue(cos.isInMemory());
        cos.close();
        assertFalse(cos.done);
    }

    @Test
    public void inFile() throws IOException {
        ContentOutputStream cos = new ContentOutputStream(10, Curl.tmpDir);
        cos.write(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 });
        assertFalse(cos.done);
        assertFalse(cos.isInMemory());

    status_code, body = _bench_post_json(
        benchmark,
        client,
        "/sync/validated",
        json={"name": "foo", "value": 123},
    )
    assert status_code == 200
    assert body == b'{"name":"foo","value":123,"dep":42}'


def test_sync_return_dict_without_response_model(benchmark, client: TestClient) -> None:

def get_current_user(oauth_header: str | None = Security(reusable_oauth2)):
    if oauth_header is None:
        return None
    user = User(username=oauth_header)
    return user


@app.post("/login")
def login(form_data: OAuth2PasswordRequestFormStrict = Depends()):
    return form_data


@app.get("/users/me")
def read_users_me(current_user: User | None = Depends(get_current_user)):
    if current_user is None:

class Token(BaseModel):
    access_token: str
    token_type: str


class TokenData(BaseModel):
    username: str | None = None
    scopes: list[str] = []


class User(BaseModel):
    username: str
    email: str | None = None
    full_name: str | None = None
    disabled: bool | None = None


class UserInDB(User):
    hashed_password: str


password_hash = PasswordHash.recommended()

Раніше ми мали таку анотацію типу:

```Python
q: str | None = None
```

Тепер ми загорнемо її у `Annotated`, і отримаємо:

```Python
q: Annotated[str | None] = None
```

Обидві ці версії означають одне й те саме: `q` — це параметр, який може бути `str` або `None`, і за замовчуванням має значення `None`.

А тепер переходимо до цікавого! 🎉