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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_prediction(self):
 """Compute the combined prediction and prediction weight for this action set. The combined prediction is the weighted average of the individual predictions of the classifiers. The combined prediction weight is the sum of the individual prediction weights of the classifiers. Usage: Do not call this method directly. Use the prediction and/or prediction_weight properties instead. Arguments: None Return: None """

        total_weight = 0
        total_prediction = 0
        for rule in self._rules.values():
            total_weight += rule.prediction_weight
            total_prediction += (rule.prediction *
                                 rule.prediction_weight)
        self._prediction = total_prediction / (total_weight or 1)
        self._prediction_weight = total_weight