Solved by aguennecjacq in post #2 
              
              
                To do so, you need to modify VGG.features. It is a nn.Sequential object and so all you need to do is modify the layers this specific object, you don’t need to modify the forward. Something of the following: 
model = torchvision.model.vgg19(pretrained=True)
feats_list = list(model.features)
new_feats…