diff --git a/tutorials/key_differences_between_python_2_and_3.ipynb b/tutorials/key_differences_between_python_2_and_3.ipynb
index a1afba9..c830a92 100644
--- a/tutorials/key_differences_between_python_2_and_3.ipynb
+++ b/tutorials/key_differences_between_python_2_and_3.ipynb
@@ -1,7 +1,7 @@
 {
  "metadata": {
   "name": "",
-  "signature": "sha256:a91d66ae5e233f325b262961102505a8bdaee3ad1a251f061dee9cd68c0aaeac"
+  "signature": "sha256:6381ed57a43484d7eb056ed84635101d586f95e11bbc8904b58f8d2c3c5693c3"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -900,7 +900,7 @@
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "Another thing worth mentioning is that `range` got a \"new\" `__contains__` method in Python 3.x (thanks to [yegle](), who pointed this out).  The `__contains__` method can speedup \"look-ups\" in Python 3.x `range` significantly for integer and bolean types.\n"
+      "Another thing worth mentioning is that `range` got a \"new\" `__contains__` method in Python 3.x (thanks to [Yuchen Ying](https://github.com/yegle), who pointed this out).  The `__contains__` method can speedup \"look-ups\" in Python 3.x `range` significantly for integer and bolean types.\n"
      ]
     },
     {