Trong trường hợp này, nó là một hàm `async`.

---

Bạn cũng có thể định nghĩa nó như là một hàm thông thường thay cho `async def`:

```Python hl_lines="7"
{!../../docs_src/first_steps/tutorial003.py!}
```

/// note

Nếu bạn không biết sự khác nhau, kiểm tra [Async: *"Trong khi vội vàng?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

pkg syscall (freebsd-arm64), func Statfs(string, *Statfs_t) error
pkg syscall (freebsd-arm64), func StringSlicePtr //deprecated
pkg syscall (freebsd-arm64), func StringSlicePtr([]string) []*uint8
pkg syscall (freebsd-arm64), func Sync() error
pkg syscall (freebsd-arm64), func Syscall(uintptr, uintptr, uintptr, uintptr) (uintptr, uintptr, Errno)

pkg syscall (darwin-arm64), func Statfs(string, *Statfs_t) error
pkg syscall (darwin-arm64), func StringSlicePtr //deprecated
pkg syscall (darwin-arm64), func StringSlicePtr([]string) []*uint8
pkg syscall (darwin-arm64), func Sync() error
pkg syscall (darwin-arm64), func Syscall(uintptr, uintptr, uintptr, uintptr) (uintptr, uintptr, Errno)

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(
            alias="item-query",
            title="Query string",
            description="Query string for the items to search in the database that have a good match",
            min_length=3,
            max_length=50,

    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, importance: int = Body()):
    results = {"item_id": item_id, "item": item, "user": user, "importance": importance}

class CommonQueryParams:
    def __init__(self, q: str | None = None, skip: int = 0, limit: int = 100):
        self.q = q
        self.skip = skip
        self.limit = limit


@app.get("/items/")
async def read_items(commons=Depends(CommonQueryParams)):
    response = {}
    if commons.q:
        response.update({"q": commons.q})
    items = fake_items_db[commons.skip : commons.skip + commons.limit]

from datetime import datetime, time, timedelta
from typing import Annotated
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: Annotated[datetime, Body()],
    end_datetime: Annotated[datetime, Body()],
    process_after: Annotated[timedelta, Body()],
    repeat_at: Annotated[time | None, Body()] = None,
):

@app.post(
    "/items/",
    response_model=Item,
    summary="Create an item",
    description="Create an item with all the information, name, description, price, tax and a set of unique tags",
)
async def create_item(item: Item):

            openIdConnectUrl=openIdConnectUrl, description=description
        )
        self.scheme_name = scheme_name or self.__class__.__name__
        self.auto_error = auto_error

    async def __call__(self, request: Request) -> Optional[str]:
        authorization = request.headers.get("Authorization")
        if not authorization:
            if self.auto_error:
                raise HTTPException(

    if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(
    email: str, background_tasks: BackgroundTasks, q: str = Depends(get_query)
):
    message = f"message to {email}\n"
    background_tasks.add_task(write_log, message)