I like this plotting from json behaviour, but how about showing node labels?

How do I show the node labels??

I have something I like, but I want to show the node labels.
https://gist.github.com/bshambaugh/9b9b4f89c321deea8f1f8b5c9948048d

The code at http://localhost/sigma.js/br-examples/custom-node-renderer.html seems to show the node labels by default, what is the code that does this???