I created a model (model_final) that calls another model (model_first_step). So to run model_final, I need to also have the model_first_step. You can find both models and the workflow here for download, but the question should be understandable without this context.
How can I include the model_first_step into the model_final? Of course, I could copy the whole workflow inside model_first_step into model_final, but doing it manually would be cumbersome. Is there a way to automatize this, so I don't have to share two files (two models)?
The model on the right is called inside the model on the left:

