RFC: Notebook examples

I notice the documentation a bit lacking and I've decided I need to do my part; 
I am particularly interested in example form pointers, I've copied an existing example and modified it to my content but I don't know if there is preferred format or functionality/progression guidelines.

Also, this is the first time I've written in whatever syntax the docs are generated from, Would appreciate some pointers on best editors and how to setup a build server for previewing generated docs.

The non-code content is straight up plagiarized from https://developer.gnome.org/gtk3/stable/GtkNotebook.html#GtkNotebook.description

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All that said, I don't wish to put extraordinary amount of time or effort into my contributions.