It writes an empty hash to the file before calling I18n.translate() in order to distinguish between translations in this custom scripts.yml (which is regenerated by this task) versus translations in the more permanent data.yml (as is the case for the hard-coded levels). if it's not emptied out, it will think the translation is already present and skip it, causing the generated hash to be empty. There's probably a cleaner way to do this if you have a suggestion.