foldrWithKey :: (k -> Set a -> b -> b) -> b -> Multimap k a -> b
foldrWithKey f b (Multimap m) = Map.foldrWithKey f b m
foldrWithKey :: (k -> Set a -> b -> b) -> b -> Multimap k a -> b
foldrWithKey f b (Multimap m) = Map.foldrWithKey f b m
foldrWithKey f b (Multimap m) = Map.foldrWithKey f b m