diff --git a/online_judges/utopian_tree/test_utopian_tree.py b/online_judges/utopian_tree/test_utopian_tree.py
index 2af3cd2..6d11808 100644
--- a/online_judges/utopian_tree/test_utopian_tree.py
+++ b/online_judges/utopian_tree/test_utopian_tree.py
@@ -4,9 +4,10 @@ from nose.tools import assert_equal
 class TestUtopianTree(object):
 
     def test_utopian_tree(self):
-        assert_equal(calc_utopian_tree_height(0), 1)
-        assert_equal(calc_utopian_tree_height(1), 2)
-        assert_equal(calc_utopian_tree_height(4), 7)
+        solution = Solution()
+        assert_equal(solution.calc_utopian_tree_height(0), 1)
+        assert_equal(solution.calc_utopian_tree_height(1), 2)
+        assert_equal(solution.calc_utopian_tree_height(4), 7)
         print('Success: test_utopian_tree')
 
 
diff --git a/online_judges/utopian_tree/utopian_tree_challenge.ipynb b/online_judges/utopian_tree/utopian_tree_challenge.ipynb
index e09696e..a91cbc2 100644
--- a/online_judges/utopian_tree/utopian_tree_challenge.ipynb
+++ b/online_judges/utopian_tree/utopian_tree_challenge.ipynb
@@ -72,9 +72,11 @@
    },
    "outputs": [],
    "source": [
-    "def calc_utopian_tree_height(cycles):\n",
-    "    # TODO: Implement me\n",
-    "    pass"
+    "class Solution(object):\n",
+    "\n",
+    "    def calc_utopian_tree_height(self, cycles):\n",
+    "        # TODO: Implement me\n",
+    "        pass"
    ]
   },
   {
@@ -101,9 +103,10 @@
     "class TestUtopianTree(object):\n",
     "\n",
     "    def test_utopian_tree(self):\n",
-    "        assert_equal(calc_utopian_tree_height(0), 1)\n",
-    "        assert_equal(calc_utopian_tree_height(1), 2)\n",
-    "        assert_equal(calc_utopian_tree_height(4), 7)\n",
+    "        solution = Solution()\n",
+    "        assert_equal(solution.calc_utopian_tree_height(0), 1)\n",
+    "        assert_equal(solution.calc_utopian_tree_height(1), 2)\n",
+    "        assert_equal(solution.calc_utopian_tree_height(4), 7)\n",
     "        print('Success: test_utopian_tree')\n",
     "\n",
     "\n",
@@ -128,21 +131,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.10"
+   "pygments_lexer": "ipython3",
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,
diff --git a/online_judges/utopian_tree/utopian_tree_solution.ipynb b/online_judges/utopian_tree/utopian_tree_solution.ipynb
index d9c7af0..d8ee1b3 100644
--- a/online_judges/utopian_tree/utopian_tree_solution.ipynb
+++ b/online_judges/utopian_tree/utopian_tree_solution.ipynb
@@ -79,16 +79,18 @@
    },
    "outputs": [],
    "source": [
-    "def calc_utopian_tree_height(cycles):\n",
-    "    height = 1\n",
-    "    if cycles == 0:\n",
-    "        return height\n",
-    "    for i in range(1, cycles+1):\n",
-    "        if i % 2 == 1:\n",
-    "            height *= 2\n",
-    "        else:\n",
-    "            height += 1\n",
-    "    return height"
+    "class Solution(object):\n",
+    "\n",
+    "    def calc_utopian_tree_height(self, cycles):\n",
+    "        height = 1\n",
+    "        if cycles == 0:\n",
+    "            return height\n",
+    "        for i in range(1, cycles+1):\n",
+    "            if i % 2 == 1:\n",
+    "                height *= 2\n",
+    "            else:\n",
+    "                height += 1\n",
+    "        return height"
    ]
   },
   {
@@ -122,9 +124,10 @@
     "class TestUtopianTree(object):\n",
     "\n",
     "    def test_utopian_tree(self):\n",
-    "        assert_equal(calc_utopian_tree_height(0), 1)\n",
-    "        assert_equal(calc_utopian_tree_height(1), 2)\n",
-    "        assert_equal(calc_utopian_tree_height(4), 7)\n",
+    "        solution = Solution()\n",
+    "        assert_equal(solution.calc_utopian_tree_height(0), 1)\n",
+    "        assert_equal(solution.calc_utopian_tree_height(1), 2)\n",
+    "        assert_equal(solution.calc_utopian_tree_height(4), 7)\n",
     "        print('Success: test_utopian_tree')\n",
     "\n",
     "\n",
@@ -159,21 +162,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.10"
+   "pygments_lexer": "ipython3",
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,