You will then be able to use the auto classes like you would usually do!

If your NewModelConfig is a subclass of [~transformers.PretrainedConfig], make sure its
model_type attribute is set to the same key you use when registering the config (here "new-model").
Likewise, if your NewModel is a subclass of [PreTrainedModel], make sure its
config_class attribute is set to the same class you use when registering the model (here
NewModelConfig).