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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 set_append(input_set, item):
 # type: (set, Any) -> set """ Appends in-place the given item to the set. If the item is a list, all elements are added to the set. :param input_set: An existing set :param item: The item or list of items to add :return: The given set """

    if item:
        if isinstance(item, (list, tuple)):
            input_set.update(item)
        else:
            input_set.add(item)
    return input_set