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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):
 """ Return a new RDD by applying a function to each partition of this RDD. [3, 7] """

        def func(s, iterator):
            return f(iterator)
        return self.mapPartitionsWithIndex(func, preservesPartitioning)