diff --git a/staging/arrays_strings/reverse_words/reverse_words_challenge.ipynb b/staging/arrays_strings/reverse_words/reverse_words_challenge.ipynb
index 92f5447..c0257ad 100644
--- a/staging/arrays_strings/reverse_words/reverse_words_challenge.ipynb
+++ b/staging/arrays_strings/reverse_words/reverse_words_challenge.ipynb
@@ -103,7 +103,7 @@
     "from nose.tools import assert_equal\n",
     "\n",
     "class UnitTest (object):\n",
-    "    def testReverseWords(self):\n",
+    "    def testReverseWords(self, func):\n",
     "            assert_equal(func('the sun is hot'), 'eht nus si toh')\n",
     "            assert_equal(func(''), None)\n",
     "            assert_equal(func('123 456 789'), '321 654 987')\n",
@@ -148,4 +148,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 0
-}
\ No newline at end of file
+}