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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 extra(self, response):
 """Add extra info to response."""

        if 'facets' in self.hits:
            response['_facets'] = self.hits['facets']
        if 'aggregations' in self.hits:
            response['_aggregations'] = self.hits['aggregations']