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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 reduce(self, f):
 """ Reduces the elements of this RDD using the specified commutative and associative binary operator. Currently reduces partitions locally. 15 10 Traceback (most recent call last):
 ValueError: Can not reduce() empty RDD """

        f = fail_on_stopiteration(f)

        def func(iterator):
            iterator = iter(iterator)
            try:
                initial = next(iterator)
            except StopIteration:
                return
            yield reduce(f, iterator, initial)

        vals = self.mapPartitions(func).collect()
        if vals:
            return reduce(f, vals)
        raise ValueError("Can not reduce() empty RDD")