code: def register(cls):
      
      registry_entry = RegistryEntry(category = cls.category, namespace = cls.namespace, name = cls.name, cls=cls)
      if registry_entry not in registry and not exists_in_registry(cls.category, cls.namespace, cls.name):
          registry.append(registry_entry)
      else:
          log.warn("Class {0} already in registry".format(cls))
docs: Register a given model in the registry