About Rasa 3 code reference

Hello everyone:

Recently I upgraded to Rasa 3. I am developing models with Rasa NLU using Python scripts in my backend. In this setup, I trained models in Rasa 2.x using Trainer() class, and then perform inference by parsing text with Interpreter() class. However I cannot find these classes in the new code reference because they are not located in module rasa.nlu.model anymore (find the code reference here)

How can I realize where the classes are located, or which classes replaced the old ones and how to use them? Can anyone help me?

Thank you.