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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 max(self, key=None):
 """ Find the maximum item in this RDD. :param key: A function used to generate key for comparing 43.0 5.0 """

        if key is None:
            return self.reduce(max)
        return self.reduce(lambda a, b: max(a, b, key=key))