code: def build_losers_to_winners_map(objects)
        inverse = {}
        objects.each do |id,object|
          (inverse[object.to_h.except(:_id)] ||= []) << id
        end
  
        {}.tap do |map|
          inverse.values.each do |ids|
            ids.drop(1).each do |id|
              map[id] = ids[0]
            end
          end
        end
      end
docs: For each object, map its ID to the ID of its duplicate, if any.
  
   @param [Hash] objects a hash of scraped objects keyed by ID
   @return [Hash] a mapping from an object ID to the ID of its duplicate