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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 pwm_max_score(self):
 """Return the maximum PWM score. Returns ------- score : float Maximum PWM score. """

        if self.max_score is None:
            score = 0
            for row in self.pwm:
                score += log(max(row) / 0.25 + 0.01)
            self.max_score = score
        
        return self.max_score