Fatal Error after Update to latest WordPress version

Hello,

after updating to the latest wordpress version I get the following error message:

Fatal error: Cannot redeclare has_shortcode() (previously declared in /www/htdocs/w00d80c5/oranke-optik/wp-includes/shortcodes.php:166) in /www/htdocs/w00d80c5/oranke-optik/wp-content/themes/balance/functions.php on line 472

What can I do now?