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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def categorize(func: Union[Callable, Iterable], category: str) -> None: """Categorize a function. The help command output will group this function under the specified category heading :param func: function to categorize :param category: category to put it in """

    if isinstance(func, Iterable):
        for item in func:
            setattr(item, HELP_CATEGORY, category)
    else:
        setattr(func, HELP_CATEGORY, category)