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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 remove_by_score(self, low, high=None):
 """ Remove elements from the ZSet by their score. :param low: Lower bound. :param high: Upper bound. """

        if high is None:
            high = low
        return self.database.zremrangebyscore(self.key, low, high)