The following call to load load and parse the file, either with KAML or JSON, depending on the file extension of ".kaml" or ".json"
The following series of statements will first print out the hobbies specified, then it will add a new hobby to the node structure, and print out the revised hobby list. If you comment out the entire hobby list from the file (and make sure to copy the file to the build directory), this will still work because of the line that checks if the hobbies node is a unTyped node, and if it is, it will set the node to be a list.
The following shows how you can take any node of the structure and generate JSON from that point.