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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 attr_category_postprocess(get_attr_category_func):
 """Unifies attr_category to a tuple, add AttrCategory.SLOT if needed."""

    @functools.wraps(get_attr_category_func)
    def wrapped(
        name: str, attr: Any, obj: Any
    ) -> Tuple[AttrCategory, ...]:
        category = get_attr_category_func(name, attr, obj)
        category = list(category) if isinstance(category, tuple) else [category]
        if is_slotted_attr(obj, name):
            # Refactoring all tuples to lists is not easy
            # and pleasant. Maybe do this in future if necessary
            category.append(AttrCategory.SLOT)
        return tuple(category)

    return wrapped