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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 cogroup(self, other, numPartitions=None):
 """ Return a new DStream by applying 'cogroup' between RDDs of this DStream and `other` DStream. Hash partitioning is used to generate the RDDs with `numPartitions` partitions. """

        if numPartitions is None:
            numPartitions = self._sc.defaultParallelism
        return self.transformWith(lambda a, b: a.cogroup(b, numPartitions), other)