def list_to_comma_separated(items: list[str]) -> str: """Given a list of items, returns a comma separated string of the items""" return ",".join(items) def comma_separated_to_list(comma_separated: str) -> list[str]: """Given a comma separated string, returns a list of the comma separated items. Strips whitespace from each item, drops any items that are whitespace only """ items = comma_separated.split(",") if comma_separated else [] non_empty_items = [item.strip() for item in items if item.strip()] return non_empty_items def comma_separated_to_set(comma_separated: str) -> set[str]: """Given a comma separated string, returns a set of the comma separated items. Strips whitespace from each item, drops any items that are whitespace only """ items = comma_separated.split(",") if comma_separated else [] non_empty_items = {item.strip() for item in items if item.strip()} return non_empty_items