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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 _ensure_append(self, new_items, append_to, index=0):
 """Ensure an item is appended to a list or create a new empty list :param new_items: the item(s) to append :type new_items: list(obj) :param append_to: the list on which to append the items :type append_to: list() :param index: index of the list on which to append the items :type index: int """

        append_to = append_to or []
        append_to.insert(index, new_items)
        return append_to