evant, irrelevant = propagate_conv_linear(relevant, irrelevant, mods[3])
    relevant, irrelevant = propagate_relu(relevant, irrelevant, F.relu)

    relevant, irrelevant = propagate_conv_linear(relevant, irrelevant, mods[4])

    return relevant, irrelevant


def cd_track_vgg(blob, im_torch, model, model_type=&#39;vgg&#39;):
    &#39;&#39;&#39;This implementation of cd is very long so that we can view CD at intermediate layers
    In reality, one should use the loop contained in the above cd function
    &