@Override
            public Node objectNode(ObjectNode node) {
                Map<StringNode, Node> members = new TreeMap<>(keyComparator);
                node.getMembers().forEach((k, v) -> members.put(k, sortNode(v, keyComparator)));
                return new ObjectNode(members, node.getSourceLocation());
            }
Returns a node with sorted keys and sorted keys of all nested object
nodes using a custom comparator.

@param keyComparator Compares keys.
@return Returns the node in which all object nodes have sorted keys.
smithy-model/src/main/java/software/amazon/smithy/model/node/Node.java