code: def min_depth(self, root):
      """
      :type root: TreeNode
      :rtype: int
      """
      if root is None:
          return 0
      if root.left is not None or root.right is not None:
          return (
              max(self.minDepth(root.left), self.minDepth(root.right))
              + 1
          )
      return (
          min(self.minDepth(root.left), self.minDepth(root.right)) + 1
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: min_depth(root) and returns: unknown, int, unknown