WGAN-GP implementation incompatible with TensorFlow 2.x

[DCtheTall]

FWIW the WGAN-GP implementation in this repo, as the issue title suggests, breaks when you try to use TensorFlow 2.x. When you try to use the current implementation K.gradients() returns None when computing the gradient penalty loss.

I am not sure if this book is intentionally restricted to TF 1.x, but it might be nice to mention this breakage somewhere?

There's an implementation of a WGAN-GP using Keras and TensorFlow here (this code has the WGAN-GP extend the keras.models.Model class but I don't think that is actually necessary).

[arisliang]

Have you tried the tensorflow_2 branch?