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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 tune(self, verbose=None):
 """ Tuning initial slice width parameter """

        if not self._tune:
            return False
        else:
            self.w_tune.append(
                abs(self.stochastic.last_value - self.stochastic.value))
            self.w = 2 * (sum(self.w_tune) / len(self.w_tune))
            return True