code: def deserialize(data):
      def build_tree():
          val = next(vals)
          if val == "#":
              return None
          node = TreeNode(int(val))
          node.left = build_tree()
          node.right = build_tree()
          return node
  
      vals = iter(data.split())
      return build_tree()
  
label_desc: Use image node_id 2 for calling a global function with example usage: deserialize(data) and returns: build_tree, node, None