Cli

def main(
    argv: Sequence[str] | None = None,
) -> None:
    """Run the command-line interface."""

    parser = _create_parser()
    args = parser.parse_args(argv)

    # No input/output parameters: start GUI.
    if args.input is None and args.output is None:
        run_gui()
        return

    # Input and output must be specified together.
    if args.input is None or args.output is None:
        parser.error("input and output must be specified together")

    identifiers = read_identifiers(args.input)
    processflow = ProcessFlow(
        morningstar=args.morningstar,
        motleyfool=args.motleyfool,
        seekingalpha=args.seekingalpha,
        yahoo=args.yahoo
    )
    securities = processflow.run(identifiers)
    write_excel(
        securities,
        args.output,
        classifications=get_classification_output(
            args.morningstar,
            args.motleyfool or args.seekingalpha,
        ),
        provider_details=True,
    )