while(len(node_list) != 1):
        # Create the new node based on the lowest two
        temp_node = Node(left=node_list[0], right=node_list[1])
        temp_node.number = node_list[0].number + node_list[1].number

        # Remove the lowest two
        del node_list[1]
        del node_list[0]

        # Push the new node in
        node_list.append(temp_node)

        # Resort
        node_list.sort(key=lambda node: node.number)