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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 min(self, key=None):
 """ Find the minimum item in this RDD. :param key: A function used to generate key for comparing 2.0 10.0 """

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