There are 2 ways to use this repository, manipulating the pydantic classes directly and having to bother with the ids or using object classes, easier to handle at runtime. The object classes examples are here
Code examples to generate C# Yarrow file in .Net Core and .Net Framework here.
Code examples in Python and .Net here.
Code examples in Python with output JSON file here.
Code example in Python on how to fill an annotation with keypoint information here