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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 flatMap(self, f, preservesPartitioning=False):
 """Apply function f and flatten. :param f: mapping function :rtype: DStream """

        return self.mapPartitions(
            lambda p: (e for pp in p for e in f(pp)),
            preservesPartitioning,
        )