      "        node7 = bst.insert(7)\n",
      "        node6 = bst.insert(6)\n",
      "        node9 = bst.insert(9)\n",
      "        result = bst.invert_tree()\n",
      "        assert_equal(result, root)\n",
      "        assert_equal(result.left, node7)\n",
      "        assert_equal(result.right, node2)\n",
      "        assert_equal(result.left.left, node9)\n",
      "        assert_equal(result.left.right, node6)\n",
      "        assert_equal(result.right.left, node3)\n",
      "        assert_equal(result.right.right, node1)\n",
      "        print('Success: test_invert_tree')\n",
      "\n",
      "\n",
      "def main():\n",
      "    test = TestInvertTree()\n",
 
</s> remove     "        assert_equal(result, root)\n",
    "        assert_equal(result.left, node7)\n",
    "        assert_equal(result.right, node2)\n",
    "        assert_equal(result.left.left, node9)\n",
    "        assert_equal(result.left.right, node6)\n",
    "        assert_equal(result.right.left, node3)\n",
    "        assert_equal(result.right.right, node1)\n",
 </s> add     "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n", </s> remove         assert_equal(result, root)
        assert_equal(result.left, node7)
        assert_equal(result.right, node2)
        assert_equal(result.left.left, node9)
        assert_equal(result.left.right, node6)
        assert_equal(result.right.left, node3)
        assert_equal(result.right.right, node1)
 </s> add         self.assertEqual(result, root)
        self.assertEqual(result.left, node7)
        self.assertEqual(result.right, node2)
        self.assertEqual(result.left.left, node9)
        self.assertEqual(result.left.right, node6)
        self.assertEqual(result.right.left, node3)
        self.assertEqual(result.right.right, node1) </s> remove     "        assert_equal(bst.find_second_largest(), node7)\n",
 </s> add     "        self.assertEqual(bst.find_second_largest(), node7)\n", </s> remove     "        assert_equal(bst.find_second_largest(), node7)\n",
 </s> add     "        self.assertEqual(bst.find_second_largest(), node7)\n", </s> remove     "        assert_equal(bst.check_balance(), True)\n",
 </s> add     "        self.assertEqual(bst.check_balance(), True)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
      "        node7 = bst.insert(7)\n",
      "        node6 = bst.insert(6)\n",
      "        node9 = bst.insert(9)\n",
      "        result = bst.invert_tree()\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
    "        self.assertEqual(result, root)\n",
    "        self.assertEqual(result.left, node7)\n",
    "        self.assertEqual(result.right, node2)\n",
    "        self.assertEqual(result.left.left, node9)\n",
    "        self.assertEqual(result.left.right, node6)\n",
    "        self.assertEqual(result.right.left, node3)\n",
    "        self.assertEqual(result.right.right, node1)\n",
      "        print('Success: test_invert_tree')\n",
      "\n",
      "\n",
      "def main():\n",
      "    test = TestInvertTree()\n",
keep keep keep keep replace replace replace replace replace replace replace keep keep keep keep keep
 #273: Remove nose dependency for graphs_trees/ (#277) 
graphs_trees/invert_tree/invert_tree_challenge.ipynb