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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 compute_refresh_time(self):
 """ Compute the refresh period for the given expiration delay """

        if self.z == 0:
            self.z = 1E-10
        s = float(self.expiration) * (1.0/(self.nbr_bits)) * (1.0/(self.counter_init - 1 + (1.0/(self.z * (self.nbr_slices + 1)))))
        return s