Setting weights as adapter weights

I have a custom model with a T5 backbone and an additional GNN-based module. I would like to save and load just the module weights. As I understand, Transformers now has ways to handle this because of PEFT methods. How can I set my additional weights to be labeled as adapter weights for seamless saving and loading using the transformers methods (e.g., save_pretrained() and PeftModel.from_pretrained())?