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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 iter_non_intersecting(self, iterable, key=None, descending=False):
 """Like `iter_intersect_test`, but returns non-intersections only. Returns: An iterator that returns items from `iterable` that don't intersect. """

        return _ContainsVersionIterator(self, iterable, key, descending,
            mode=_ContainsVersionIterator.MODE_NON_INTERSECTING)