Natural sort / ordering wp_dropdown_categories

not the best way (at least if you have a lot of tags)

add_filter('get_terms_orderby', 'get_terms_orderby_natural_slug',10,2);
wp_dropdown_categories( 'taxonomy=week&hierarchical=1&orderby=slug' );
remove_filter('get_terms_orderby', 'get_terms_orderby_natural_slug');

function get_terms_orderby_natural_slug($orderby, $args){
    $orderby = "SUBSTR({$orderby} FROM 1 FOR 5), CAST(SUBSTR({$orderby} FROM 6) AS UNSIGNED), SUBSTR({$orderby} FROM 6)";
    return $orderby;
}

but still this is a way to do that…