Hmm, I didn’t try the code yesterday and just changed the line from a residual network.
Now I tried it, and got the same error as you. It seems that you can get just the model, but not the weights of it. Which actually contradicts the documentation when it is written that you can give the pretrained argument.
As @Crazyai said, you can refer to that issue and download the model from github. However, bear in mind that they are not planning to release the version with batch normalization. Alternately, use a residual network and finetune it, probably getting even better results than with VGG.