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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 generate_additional_context(self, matching_datasets):
 """Return top tags for a source."""

        top_tags = Tag.objects.filter(
            dataset__in=matching_datasets
        ).annotate(
            tag_count=Count('word')
        ).order_by('-tag_count')[:3]

        return {
            'top_tags': top_tags
        }