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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 lookup(self, key):
 """ Return the list of values in the RDD for key `key`. This operation is done efficiently if the RDD has a known partitioner by only searching the partition that the key maps to. [42] [42] [] ['c'] """

        values = self.filter(lambda kv: kv[0] == key).values()

        if self.partitioner is not None:
            return self.ctx.runJob(values, lambda x: x, [self.partitioner(key)])

        return values.collect()