Get filepath using Flet in python

I am using Flet 0.80.4 with Python 3.11.

The user should be able to upload a file via a button. I want to process this file with Polars or Pandas. I found some examples of how to handle file uploads, but they rely on the on_result method, which has been deprecated in the current Flet version.

I am looking for a way to either:

1. Get the full path to the uploaded file, or
2. Use an alternative approach to work with the uploaded file directly in memory (without saving it to a temporary directory).

My func:

def main(page: ft.Page):
    page.title = 'Title'
    page.window.width = 450
    page.window.height = 350
    page.vertical_alignment = ft.MainAxisAlignment.CENTER
    page.horizontal_alignment = ft.CrossAxisAlignment.CENTER

    async def handle_pick_files(e: ft.Event[ft.Button]):
        file = await ft.FilePicker().pick_files(
            file_type=ft.FilePickerFileType.CUSTOM,
            allowed_extensions=['xlsx'],
        )
        selected_files.value = (
            ", ".join(map(lambda f: f.name, file))
        )

    load_file_button = ft.Button(
        content='UPLOAD',
        icon=ft.Icons.UPLOAD_FILE,
        on_click=handle_pick_files,
    )

    page.add(
        ft.Row(
            controls=[
                load_file_button,
                selected_files := ft.Text(),
            ],
            alignment=ft.MainAxisAlignment.CENTER
        ),
    )


ft.run(main)