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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 got_score(self, score):
 """Update the best score if the new score is higher, returning the change."""

        if score > self._score:
            delta = score - self._score
            self._score = score
            self._score_changed = True
            self.save()
            return delta
        return 0