- You can find the source code under path: https://github.com/DataCanvasIO/YLearn/blob/main/ylearn/causal_model/model.py - Please firstly read the related document and understand the function code - Please build a unit test named '**model_test.py**' to test the function and **save it under path**: https://github.com/DataCanvasIO/YLearn/tree/main/tests - The requirement is to reach **at least 70% code coverage**