Fatal error: Uncaught Error: Interface 'UsingInterfaces\ProductInterface' not found in /home/itscm/dev.its.cm/webserivesits/vendor/zircote/swagger-php/Examples/using-interfaces/Product.php:8 Stack trace: #0 {main} thrown in /home/itscm/dev.its.cm/webserivesits/vendor/zircote/swagger-php/Examples/using-interfaces/Product.php on line 8