fun <K, V> treeMap(store: Store, keySerializer: GroupSerializer<K>, valueSerializer: GroupSerializer<V>, comparator: Comparator<K> = keySerializer, leafNodeSize: Int = CC.BTREEMAP_MAX_NODE_SIZE*3/4, dirNodeSize: Int = CC.BTREEMAP_MAX_NODE_SIZE*3/4): Sink<<ERROR CLASS><K, V>, Unit>