python – Problen in 3D GAN which allows him to generate whole blocks instead of real 3D forms

I'm trying to launch this 3D GAN. I read about it in the book (Generative Adversarial Networks Projects on packt.com). In the end, the author suggested that there is a problem that needs to be solved for the gan to produce a correct 3D. objects, I can not find this error and the generator continues to produce whole blocks instead of 3D objects (link to code-https: //github.com/PacktPublishing/Generative-Adversarial-Networks-Projects/ blob / master / Chapter 02 / run.py)

I have tried different hyperparameters but still no luck

Link to code-https: //github.com/PacktPublishing/Generative-Adversarial-Networks-Projects/blob/master/Chapter02/run.py

That's the result that I get