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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_count(self):
 """ Returns the total number of votes cast across all the poll's options. """

        return Vote.objects.filter(
            content_type=ContentType.objects.get(app_label='poll', model='polloption'),
            object_id__in=[o.id for o in self.polloption_set.all()]
        ).aggregate(Sum('vote'))['vote__sum'] or 0