Grader output error

That is not a failure of the grader: that is a failure of that test in the notebook. So your two_layer_model code does not return the correct return values. Did you copy that solution from github? If so, you may have gotten an old version of the notebook. They changed the way this works in April 2021, so solutions from before that don’t work.

Please carefully compare your return statement to what is expected there. If you want to get a clean copy of the notebook to see how that code was given to you, there is a topic about that on the DLS FAQ Thread.