      "        with captured_output() as (out, err):\n",
      "            root.post_order_traversal(sys.stdout.write)\n",
      "            assert_equal(out.getvalue().strip(), '13285')\n",
      "\n",
      "        with captured_output() as (out, err):\n",
      "            root.bfs(sys.stdout.write)\n",
      "            assert_equal(out.getvalue().strip(), '52813')\n",
      "\n",
      "        root = Node(1)\n",
      "        root.insert(2)\n",
      "        root.insert(3)\n",
      "        root.insert(4)\n",
      "        root.insert(5)\n",
 
</s>
      "        with captured_output() as (out, err):\n",
      "            root.post_order_traversal(sys.stdout.write)\n",
      "            assert_equal(out.getvalue().strip(), '13285')\n",
      "\n",




      "        root = Node(1)\n",
      "        root.insert(2)\n",
      "        root.insert(3)\n",
      "        root.insert(4)\n",
      "        root.insert(5)\n",
keep keep keep keep replace replace replace replace keep keep keep keep keep
 Revised dfs challenge to be more self contained for simplicity.
graphs_trees/tree_dfs/dfs_solution.ipynb