      "    def test_merge_sort(self):\n",
      "        merge_sort = MergeSort()\n",
      "\n",
      "        print('None input')\n",
      "        assert_raises(TypeError, merge_sort.sort, None)\n",
      "\n",
      "        print('Empty input')\n",
      "        assert_equal(merge_sort.sort([]), [])\n",
      "\n",
      "        print('One element')\n",
 
</s> remove     "        assert_raises(TypeError, merge_sort.sort, None)\n",
 </s> add     "        self.assertRaises(TypeError, merge_sort.sort, None)\n", </s> remove     "        assert_equal(merge_sort.sort([]), [])\n",
 </s> add     "        self.assertEqual(merge_sort.sort([]), [])\n", </s> remove     "        assert_equal(merge_sort.sort([]), [])\n",
 </s> add     "        self.assertEqual(merge_sort.sort([]), [])\n", </s> remove         assert_raises(TypeError, merge_sort.sort, None)
 </s> add         self.assertRaises(TypeError, merge_sort.sort, None) </s> remove     "class TestMergeSort(object):\n",
 </s> add     "class TestMergeSort(unittest.TestCase):\n",
    "        self.assertRaises(TypeError, merge_sort.sort, None)\n",
      "    def test_merge_sort(self):\n",
      "        merge_sort = MergeSort()\n",
      "\n",
      "        print('None input')\n",
    "        self.assertRaises(TypeError, merge_sort.sort, None)\n",
      "\n",
      "        print('Empty input')\n",
      "        assert_equal(merge_sort.sort([]), [])\n",
      "\n",
      "        print('One element')\n",
keep keep keep keep replace keep keep keep keep keep
 #273: Remove nose dependency for sorting_searching/ (#278) 
sorting_searching/merge_sort/merge_sort_challenge.ipynb