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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 vote_total(self):
 """ Calculates vote total as total_upvotes - total_downvotes. We are adding a method here instead of relying on django-secretballot's addition since that doesn't work for subclasses. """

        modelbase_obj = self.modelbase_obj
        return modelbase_obj.votes.filter(vote=+1).count() - modelbase_obj.votes.filter(vote=-1).count()