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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 coalesce(self, numPartitions, shuffle=False):
 """ Return a new RDD that is reduced into `numPartitions` partitions. [[1], [2, 3], [4, 5]] [[1, 2, 3, 4, 5]] """

        if shuffle:
            # Decrease the batch size in order to distribute evenly the elements across output
            # partitions. Otherwise, repartition will possibly produce highly skewed partitions.
            batchSize = min(10, self.ctx._batchSize or 1024)
            ser = BatchedSerializer(PickleSerializer(), batchSize)
            selfCopy = self._reserialize(ser)
            jrdd_deserializer = selfCopy._jrdd_deserializer
            jrdd = selfCopy._jrdd.coalesce(numPartitions, shuffle)
        else:
            jrdd_deserializer = self._jrdd_deserializer
            jrdd = self._jrdd.coalesce(numPartitions, shuffle)
        return RDD(jrdd, self.ctx, jrdd_deserializer)