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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 mean(self):
 """ The mean of the best results of each trial. Returns: float: mean of measured seconds Note: This is typically less informative than simply looking at the min. It is recommended to use min as the expectation value rather than mean in most cases. Example: """

        chunk_iter = chunks(self.times, self.bestof)
        times = list(map(min, chunk_iter))
        mean = sum(times) / len(times)
        return mean