How to use the flattentool.output.FORMATS.keys function in flattentool

def spreadsheet_output(spreadsheet_output_class, name):
        spreadsheet_output = spreadsheet_output_class(
            parser=parser, main_sheet_name=main_sheet_name, output_name=name
        )
        spreadsheet_output.write_sheets()

    if output_format == "all":
        if not output_name:
            output_name = "template"
        for format_name, spreadsheet_output_class in OUTPUT_FORMATS.items():
            spreadsheet_output(
                spreadsheet_output_class, output_name + FORMATS_SUFFIX[format_name]
            )

    elif output_format in OUTPUT_FORMATS.keys():  # in dictionary of allowed formats
        if not output_name:
            output_name = "template" + FORMATS_SUFFIX[output_format]
        spreadsheet_output(OUTPUT_FORMATS[output_format], output_name)

    else:
        raise Exception("The requested format is not available")

parser=parser,
            main_sheet_name=main_sheet_name,
            output_name=name,
            sheet_prefix=sheet_prefix,
        )
        spreadsheet_output.write_sheets()

    if output_format == "all":
        if not output_name:
            output_name = "flattened"
        for format_name, spreadsheet_output_class in OUTPUT_FORMATS.items():
            spreadsheet_output(
                spreadsheet_output_class, output_name + FORMATS_SUFFIX[format_name]
            )

    elif output_format in OUTPUT_FORMATS.keys():  # in dictionary of allowed formats
        if not output_name:
            output_name = "flattened" + FORMATS_SUFFIX[output_format]
        spreadsheet_output(OUTPUT_FORMATS[output_format], output_name)

    else:
        raise Exception("The requested format is not available")