Use more markdown cells in later part of jupyter notebook.

[kaitorrens]

You do a good job introducing the generative model and commenting your code. However, later on your notebook is often just sequential blocks of code and it is hard to figure out what you are doing. You need to add some markdown cells to explain the big picture of what the code will be doing and why we want to do that.

[kaitorrens]

You should clarify what the difference is between the 'testing package' and 'new MZI test' sections are, as right now I found it difficult to tell.