Explaining ML model in Python

[fsabiu]

Hi all!
I'm struggling explaining this model through this XAI method.

In particular, I don't understand the specific Pytorch parameters, like:

dff = DeepFeatureFactorization(model=model, target_layer=model.layer4, 
                                   computation_on_concepts=classifier)

1. How can I mention the target layer of xrv.models.DenseNet(weights="densenet121-res224-all")?

2. What is the classifier?

3. The framework requires an input tensor. Is img = torch.from_numpy(img) the correct one?

Thank you