def fetch(class_name, arg)
      the_class = JSS.api_object_class(class_name)
      the_class.fetch arg, api: self
    end
def fetch(class_name, arg)
      the_class = JSS.api_object_class(class_name)
      the_class.fetch arg, api: self
    end
Retrieve an object of a given class from the API
 See {APIObject.fetch}

 @param class_name[String,Symbol] The name of a JSS::APIObject subclass
   see {JSS.api_object_class}

 @return [APIObject] The ruby-instance of the object.