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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 updaten(self, rangesets):
 """ Update a rangeset with the union of itself and several others. """

        for rng in rangesets:
            if isinstance(rng, set):
                self.update(rng)
            else:
                self.update(RangeSet(rng))