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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 reduceByKey(self, func, numPartitions=None):
 """Apply reduceByKey to every RDD. :param func: reduce function to apply :param int numPartitions: number of partitions :rtype: DStream """

        return self.transform(lambda rdd: rdd.reduceByKey(func))