text: # external imports
  import nautilus
  from nautilus import APIGateway
  
  # create an api gateway with just the schema
  class RecipeBookAPIGateway(nautilus.APIGateway):
  
      @nautilus.auth_criteria('Ingredient')
      def auth_ingredient(self, model, user):
          # an ingredient can only be viewed by author
          return model.author == user
  
  # create a service manager to run the service
  manager = ServiceManager(RecipeBookAPIGateway)
  
  if __name__ == '__main__':
      manager.run()
  