code: func Get(ctx context.Context, name string, options map[string]interface{}, registry distribution.Namespace) (distribution.Namespace, error) {
  	if middlewares != nil {
  		if initFunc, exists := middlewares[name]; exists {
  			return initFunc(ctx, registry, options)
  		}
  	}
  
  	return nil, fmt.Errorf("no registry middleware registered with name: %s", name)
  }
docs: // Get constructs a RegistryMiddleware with the given options using the named backend.