Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /var/www/html/mun/vendor/jschaedl/iban-validation/Tests/IbanTest.php:17 Stack trace: #0 {main} thrown in /var/www/html/mun/vendor/jschaedl/iban-validation/Tests/IbanTest.php on line 17