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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 aggregate(self, search):
 """ Add aggregations representing the facets selected, including potential filters. """

        for f, facet in iteritems(self.facets):
            agg = facet.get_aggregation()
            agg_filter = MatchAll()
            for field, filter in iteritems(self._filters):
                if f == field:
                    continue
                agg_filter &= filter
            search.aggs.bucket(
                '_filter_' + f,
                'filter',
                filter=agg_filter
            ).bucket(f, agg)