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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, func):
 """Return a new DStream where each RDD was reduced with ``func``. :rtype: DStream """


        # avoid RDD.reduce() which does not return an RDD
        return self.transform(
            lambda rdd: (
                rdd
                .map(lambda i: (None, i))
                .reduceByKey(func)
                .map(lambda none_i: none_i[1])
            )
        )