def _io_out_adder(parser, config_dict, *args):
    """
    Add output options to the parser
    """
    in_arg_set = set(args)
    if 'io_out' in in_arg_set:
        group = parser.add_argument_group('Output Options')
        io_opt_list = ['csv', 'table', 'json', 'html', 'header', 'noheader',
            'index', 'noindex']
        default_for_output = [config_dict['io_output_type'], config_dict[
            'io_output_header'], config_dict['io_output_index']]
        msg = 'Must be one of {}'.format(repr(io_opt_list))
        group.add_argument('-o', '--output_options', nargs='+', type=str,
            dest='output_options', metavar='option', default=
            default_for_output, help=msg)
        msg = (
            "Replace NaNs with this string. A string containing 'nan' will set na_rep to numpy NaN. Current default is {}"
            .format(repr(str(config_dict['io_output_na_rep']))))
        group.add_argument('--output_na_rep', nargs=1, type=str, dest=
            'io_output_na_rep', help=msg)
