How to get plot_model to show architecture of a custom model

I found in the " Build a basic model" Lab that if I used plot_model on the custom model we created it only showed a single block. This seems like a huge disadvantage to custom models, and I’m assuming there is a way to view the architecture of a custom model.

What are some ways I could view the architecture of a custom model with something like plot model

Right, I found this link online, it seems there are quite a few tools to visualizae models around: