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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 sortBy(self, keyfunc, ascending=True, numPartitions=None):
 """ Sorts this RDD by the given keyfunc [('1', 3), ('2', 5), ('a', 1), ('b', 2), ('d', 4)] [('a', 1), ('b', 2), ('1', 3), ('d', 4), ('2', 5)] """

        return self.keyBy(keyfunc).sortByKey(ascending, numPartitions).values()