Plugin can't be activated

when I try to active Dashboard Widget Order I got a message Plugin can't be activated due to to fatal error in line 88

that's the change I've made to the php file which the same I've copied from plugin installation page:

// change the order of the widgets here
$dashboard_widgets_order_left_column[] = 'dashboard_right_now';
$dashboard_widgets_order_left_column[] = 'dashboard_recent_comments';
$dashboard_widgets_order_left_column[] = 'dashboard_incoming_links';

$dashboard_widgets_order_right_column[] = 'custom_content_dashboard_widget';
$dashboard_widgets_order_right_column[] = 'dashboard_quick_press';
$dashboard_widgets_order_right_column[] = 'dashboard_recent_drafts';
$dashboard_widgets_order_right_column[] = 'dashboard_primary';
$dashboard_widgets_order_right_column[] = 'dashboard_secondary';