code: private function getArgumentName(Request $request, ArgumentMetadata $argument): ?string
      {
          if ($request->attributes->has($argument->getName())) {
              return $argument->getName();
          }
  
          $className = lcfirst($this->stripNamespace($argument->getType()));
  
          if ($request->attributes->has($className)) {
              return $className;
          }
  
          return null;
      }
docs: Returns the argument name from the model class.