price: float
    tax: Union[float, None] = None


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


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

from datetime import datetime, time, timedelta
from uuid import UUID

from fastapi import Body, FastAPI

app = FastAPI()


@app.put("/items/{item_id}")
async def read_items(
    item_id: UUID,
    start_datetime: datetime = Body(),
    end_datetime: datetime = Body(),
    process_after: timedelta = Body(),
    repeat_at: time | None = Body(default=None),
):
    start_process = start_datetime + process_after

from fastapi import FastAPI


class ModelName(str, Enum):
    alexnet = "alexnet"
    resnet = "resnet"
    lenet = "lenet"


app = FastAPI()


@app.get("/models/{model_name}")
async def get_model(model_name: ModelName):
    if model_name is ModelName.alexnet:
        return {"model_name": model_name, "message": "Deep Learning FTW!"}

    if model_name.value == "lenet":

from typing import Annotated

from fastapi import FastAPI, Path, Query

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    *,
    item_id: Annotated[int, Path(title="The ID of the item to get", ge=0, le=1000)],
    q: str,
    size: Annotated[float, Query(gt=0, lt=10.5)],
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})
    if size:
        results.update({"size": size})

from typing import Annotated, Union

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: Annotated[
        Union[str, None],
        Query(
            title="Query string",
            description="Query string for the items to search in the database that have a good match",
            min_length=3,
        ),
    ] = None,
):

        admin = "admin"
        user = "user"

    class OtherRole(str, Enum): ...

    class User(BaseModel):
        username: str
        role: PlatformRole | OtherRole

    @app.get("/users")
    async def get_user() -> User:
        return {"username": "alice", "role": "admin"}

    client = TestClient(app)
    return client


@needs_py310
def test_get(client: TestClient):
    response = client.get("/users")

from starlette.concurrency import (  # noqa
    run_until_first_complete as run_until_first_complete,
)

_T = TypeVar("_T")


@asynccontextmanager
async def contextmanager_in_threadpool(
    cm: AbstractContextManager[_T],
) -> AsyncGenerator[_T, None]:
    # blocking __exit__ from running waiting on a free thread

Neste caso, é uma função `async`.

---

Você também pode defini-la como uma função normal em vez de `async def`:

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note | Nota

Se você não sabe a diferença, verifique o [Async: *"Com pressa?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

En este caso, es una función `async`.

---

También podrías definirla como una función normal en lugar de `async def`:

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note | Nota

Si no sabes la diferencia, Revisa la sección [Async: *"¿Tienes prisa?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

    tags: list[str] = field(default_factory=list)
    description: Union[str, None] = None
    tax: Union[float, None] = None


app = FastAPI()


@app.get("/items/next", response_model=Item)
async def read_next_item():
    return {
        "name": "Island In The Moon",
        "price": 12.99,
        "description": "A place to be playin' and havin' fun",
        "tags": ["breater"],