code: def max_height(root):
      if root is None:
          return 0
      height = 0
      queue = [root]
      while queue:
          height += 1
          level = []
          while queue:
              node = queue.pop(0)
              if node.left is not None:
                  level.append(node.left)
              if node.right is not None:
                  level.append(node.right)
          queue = level
      return height
  
label_desc: Use image node_id 1 for calling a global function with example usage: max_height(root) and returns: height, int