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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 mapPartitions(self, f, preservesPartitioning=False):
 """Map partitions. :param f: mapping function :rtype: DStream """

        return (
            self
            .mapPartitionsWithIndex(lambda i, p: f(p), preservesPartitioning)
            .transform(lambda rdd:
                       rdd.setName('{}:{}'.format(rdd.prev.name(), f)))
        )