Implementation of NVAE

[yizhe-ang]

Hi, I just came across this library and it looks awesome. Keep up the good work!

I was just wondering if a model such as the NVAE (https://arxiv.org/abs/2007.03898), i.e. a hierarchical VAE, with an inference and generative network that shares parameters with each other, will be possible to implement using the Pixyz framework.

Thank you in advance!