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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 groupBy(self, f, numPartitions=None, partitionFunc=portable_hash):
 """ Return an RDD of grouped items. [(0, [2, 8]), (1, [1, 1, 3, 5])] """

        return self.map(lambda x: (f(x), x)).groupByKey(numPartitions, partitionFunc)