Fatal error: Uncaught Error: Class "EasyRdf\RdfNamespace" not found in /var/www/html/vendor/sweetrdf/easyrdf/lib/Literal.php:145 Stack trace: #0 /var/www/html/vendor/sweetrdf/easyrdf/lib/Literal.php(328): EasyRdf\Literal::setDatatypeMapping() #1 {main} thrown in /var/www/html/vendor/sweetrdf/easyrdf/lib/Literal.php on line 145