I added super-order mod a few days ago, today I'm trying to add edit orders mod, but after uploading all the edit orders' files, I can't access the admin pages, this is what it says when I inpurt www.domain.com/admin

Fatal error: Cannot redeclare zen_get_country_id() (previously declared mydomain/admin/includes/functions/extra_functions/edit_orders.php:34) in mydomain/admin/includes/functions/extra_functions/super_orders_functions.php on line 437


when I delete one of these two files from this extra_functions folder(edit_orders.php,super_orders_functions.php ), the admin page is available again. How to solve this problem?