iterate_tree2.py

from __future__ import print_function

class Node:
  def __init__(self, name, children):
    self.name = name
    self.children = children

tree = Node(1, [
  Node(2, [
    Node(3, [
      Node(4, []),
      Node(5, [
        Node(6,[])
      ]),
    ]),
    Node(7, [
      Node(8, []),
      Node(9, []),
    ]),
  ]),
  Node(10, [
    Node(11, []),
    Node(12, [
      Node(13, []),
      Node(14, [
        Node(15, []),
      ]),
    ])
  ]),
  Node(16, []),
])

def iterate(tree, callback):
  if callback(tree):
    return
  for node in tree.children:
    if iterate(node, callback):
      return

iterate(tree, lambda node: bool(print(node.name)))

def findByName(tree, name):
  ret = [None]
  def callback(node):
    if node.name == name:
      ret[0] = node
      return True
    else:
      return False
      
  iterate(tree, callback)
  return ret[0]

print(findByName(tree, 10).name)