openapi_version: str = "3.1.0",
    summary: str | None = None,
    description: str | None = None,
    routes: Sequence[BaseRoute],
    webhooks: Sequence[BaseRoute] | None = None,
    tags: list[dict[str, Any]] | None = None,
    servers: list[dict[str, str | Any]] | None = None,
    terms_of_service: str | None = None,
    contact: dict[str, str | Any] | None = None,
    license_info: dict[str, str | Any] | None = None,

from fastapi import Cookie, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Cookies(BaseModel):
    session_id: str
    fatebook_tracker: str | None = None
    googall_tracker: str | None = None


@app.get("/items/")
async def read_items(cookies: Cookies = Cookie()):

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

    age: int | None = Field(default=None, index=True)


class Hero(HeroBase, table=True):
    id: int | None = Field(default=None, primary_key=True)
    secret_name: str


class HeroPublic(HeroBase):
    id: int


class HeroCreate(HeroBase):
    secret_name: str


class HeroUpdate(HeroBase):
    name: str | None = None
    age: int | None = None
    secret_name: str | None = None

        @app.get("/query_example/")
        def query_example(
            data: str | None = Query(
                default=None,
                example="query1",
            ),
        ):
            return data

    @app.get("/query_examples/")
    def query_examples(
        data: str | None = Query(
            default=None,
            examples=["query1", "query2"],
        ),
    ):
        return data

from fastapi import FastAPI, status
from pydantic import BaseModel

app = FastAPI()


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


@app.post("/items/", status_code=status.HTTP_201_CREATED)
async def create_item(item: Item) -> Item:

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: Annotated[CommonHeaders, Header()]):

이 경우(`Annotated`를 사용하지 않는 경우) 함수에서 기본값 `None`을 `Query()`로 바꿔야 하므로, 이제 `Query(default=None)`로 기본값을 설정해야 합니다. (최소한 FastAPI 입장에서는) 이 인자는 해당 기본값을 정의하는 것과 같은 목적을 수행합니다.

그러므로:

```Python
q: str | None = Query(default=None)
```

...위 코드는 기본값이 `None`인 선택적 매개변수를 만들며, 아래와 동일합니다:


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

하지만 `Query` 버전은 이것이 쿼리 매개변수임을 명시적으로 선언합니다.

    "default": ...,
    "default_factory": None,
    "alias": None,
    "alias_priority": None,
    "validation_alias": None,
    "serialization_alias": None,
    "title": None,
    "field_title_generator": None,
    "description": None,
    "examples": None,
    "exclude": None,
    "exclude_if": None,
    "discriminator": None,
    "deprecated": None,
    "json_schema_extra": None,
    "frozen": None,

app = FastAPI()


class UserIn(BaseModel):
    username: str
    password: str
    email: EmailStr
    full_name: str | None = None


class UserOut(BaseModel):
    username: str
    email: EmailStr
    full_name: str | None = None


@app.post("/user/", response_model=UserOut)
async def create_user(user: UserIn) -> Any: