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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 minimum(self):
 """ Finds the minimum reaction energy E_min and corresponding mixing ratio x_min. Returns: Tuple (x_min, E_min). """

        return min([(x, energy) for _, x, energy, _, _ in self.get_kinks()],
                   key=lambda i: i[1])