I am building a web application tutorial using Pony ORM. My Python is working, but feels very clunky: in particular, I’m managing date conversion by hand after fetching records, and am doing concatenate-then-split string operations to handle a one-to-many relationship where I would naturally use a JSON field. DB schema, Pony entities, my query, and my conversion code are below; I would be very grateful for advice on how to simplify this.