注意，我们在上面的代码中编写了两次`CommonQueryParams`：

//// tab | Python 3.10+

```Python
commons: Annotated[CommonQueryParams, Depends(CommonQueryParams)]
```

////

//// tab | Python 3.10+ 未使用 Annotated

/// tip | 提示

尽可能使用 `Annotated` 版本。

///

```Python
commons: CommonQueryParams = Depends(CommonQueryParams)
```

////

    </body>
</html>
"""


@app.get("/")
async def get():
    return HTMLResponse(html)


async def get_cookie_or_token(
    websocket: WebSocket,
    session: Annotated[str | None, Cookie()] = None,
    token: Annotated[str | None, Query()] = None,
):
    if session is None and token is None:
        raise WebSocketException(code=status.WS_1008_POLICY_VIOLATION)
    return session or token

@app.get("/partial-function-dependency")
async def get_partial_function_dependency(
    value: Annotated[
        str, Depends(partial(function_dependency, "partial-function-dependency"))
    ],
) -> str:
    return value


@app.get("/partial-async-function-dependency")
async def get_partial_async_function_dependency(
    value: Annotated[
        str,
        Depends(

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,
):

## Import `Path` { #import-path }

First, import `Path` from `fastapi`, and import `Annotated`:

{* ../../docs_src/path_params_numeric_validations/tutorial001_an_py310.py hl[1,3] *}

/// info

FastAPI added support for `Annotated` (and started recommending it) in version 0.95.0.

If you have an older version, you would get errors when trying to use `Annotated`.

@app.command()
def make_pr(
    *,
    language: Annotated[str | None, typer.Option(envvar="LANGUAGE")] = None,
    command: Annotated[str | None, typer.Option(envvar="COMMAND")] = None,
    github_token: Annotated[str, typer.Option(envvar="GITHUB_TOKEN")],
    github_repository: Annotated[str, typer.Option(envvar="GITHUB_REPOSITORY")],
    commit_in_place: Annotated[
        bool, typer.Option(envvar="COMMIT_IN_PLACE", show_default=True)

Use the default scope `"request"` to run the exit code after the response is sent back.

```python
from typing import Annotated

from fastapi import Depends, FastAPI

app = FastAPI()


def get_db():
    db = DBSession()
    try:
        yield db
    finally:
        db.close()


DBDep = Annotated[DBSession, Depends(get_db)]


@app.get("/items/")
async def read_items(db: DBDep):

    ```
    """

    file: Annotated[
        BinaryIO,
        Doc("The standard Python file object (non-async)."),
    ]
    filename: Annotated[str | None, Doc("The original file name.")]
    size: Annotated[int | None, Doc("The size of the file in bytes.")]
    headers: Annotated[Headers, Doc("The headers of the request.")]
    content_type: Annotated[

from typing import Annotated

from fastapi import FastAPI, File, Form, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(
    file: Annotated[bytes, File()],
    fileb: Annotated[UploadFile, File()],
    token: Annotated[str, Form()],
):
    return {
        "file_size": len(file),
        "token": token,
        "fileb_content_type": fileb.content_type,

/// info

FastAPI added support for `Annotated` (and started recommending it) in version 0.95.0.

If you have an older version, you would get errors when trying to use `Annotated`.

Make sure you [Upgrade the FastAPI version](../../deployment/versions.md#upgrading-the-fastapi-versions) to at least 0.95.1 before using `Annotated`.

///

### Import `Depends` { #import-depends }