from fastapi import FastAPI, File, UploadFile

    app = FastAPI()


    @app.post("/files/")
    async def create_file(file: Annotated[bytes, File()]):
        return {"file_size": len(file)}


    @app.post("/uploadfile/")
    async def create_upload_file(file: UploadFile):
        return {"filename": file.filename}
    ```
    """

    file: Annotated[
        BinaryIO,

    for item in items:
        if isinstance(item, str):
            resolve_file(item=item, files=files, config=config)
        elif isinstance(item, dict):
            assert len(item) == 1
            values = list(item.values())
            if not values:
                continue
            if isinstance(values[0], str):
                resolve_file(item=values[0], files=files, config=config)

    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always")
        client.get("/openapi.json")
        assert len(w) >= 2
        duplicate_warnings = [
            warning for warning in w if issubclass(warning.category, UserWarning)
        ]
        assert len(duplicate_warnings) > 0