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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 takeOrdered(self, num, key=None):
 """ Get the N elements from an RDD ordered in ascending order or as specified by the optional key function. .. note:: this method should only be used if the resulting array is expected to be small, as all the data is loaded into the driver's memory. [1, 2, 3, 4, 5, 6] [10, 9, 7, 6, 5, 4] """


        def merge(a, b):
            return heapq.nsmallest(num, a + b, key)

        return self.mapPartitions(lambda it: [heapq.nsmallest(num, it, key)]).reduce(merge)