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I have a Document-Based Cocoa Application set up using Core Data and not using Storyboards. In the Document class I have a function that creates default data. I'm currently calling this function in override init(), so every time a document is initialized, it adds the data.However, I only want to add this data when a new document is created and not at any other time (e.g. when a file is opened). How might I be able to accomplish this?