Warnings in the Custom Theme Options page in admin

[daniapa]

This warning shows every time that functions.php call to add_settings_section(...) : Warning: call_user_func() expects parameter 1 to be a valid callback, function 'pu_display_section' not found or invalid function name in C:\Xampp\htdocs\boxfantasywp\wp-admin\includes\template.php on line 1285

To solve it, you have to insert the next function in the functions.php file : function pu_display_section($section){}