public function getColumnLabel(Column $column, SectionHolder $holder, $depth = 3)
    {
        $label = sprintf('%s > %s',
            $holder->i18n_singular_name(),
            $column->NestedTitle($depth, ' > ')
        );
        
        if ($column->isSidebar()) {
            $label .= sprintf(
                ' (%s)',
                _t(__CLASS__ . '.SIDEBAR', 'Sidebar')
            );
        }
        
        return $label;
    }