my $parser = Data::XLSX::Parser->new;
    $parser->open($_xls);  # dies in module if unable to open
    $parser->add_row_event_handler(
        sub {
            my ($row) = @_;
            $csv->print( $fh_csv, $row );
        }
    );
    $parser->sheet_by_rid( 'rId'.$parser->workbook->sheet_id($_sht) );
    close $fh_csv;