from fastapi import FastAPI, File, UploadFile
from typing_extensions import Annotated

app = FastAPI()


@app.post("/files/")
async def create_file(file: Annotated[Union[bytes, None], File()] = None):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: Union[UploadFile, None] = None):

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: Annotated[bytes | None, File()] = None):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile | None = None):
    if not file:

                *path operations* in this router.

                Read more about it in the
                [FastAPI docs for Bigger Applications - Multiple Files](https://fastapi.tiangolo.com/tutorial/bigger-applications/#include-an-apirouter-with-a-custom-prefix-tags-responses-and-dependencies).

                **Example**

                ```python

    """
    `APIRouter` class, used to group *path operations*, for example to structure
    an app in multiple files. It would then be included in the `FastAPI` app, or
    in another `APIRouter` (ultimately included in the app).

    Read more about it in the
    [FastAPI docs for Bigger Applications - Multiple Files](https://fastapi.tiangolo.com/tutorial/bigger-applications/).

    ## Example

    ```python