      "\n",
      "class TestInsertionSort(object):\n",
      "\n",
      "    def test_insertion_sort(self):\n",
      "        print('None input')\n",
      "        assert_raises(TypeError, insertion_sort.sort, None)\n",
      "\n",
      "        print('Empty input')\n",
 
</s> remove     "        data = None\n",
    "        insertion_sort(data)\n",
    "        assert_equal(data, None)\n",
 </s> add     "        assert_raises(TypeError, insertion_sort.sort, None)\n", </s> remove     "        data = None\n",
    "        insertion_sort(data)\n",
    "        assert_equal(data, None)\n",
 </s> add     "        assert_raises(TypeError, insertion_sort.sort, None)\n", </s> remove     "        data = []\n",
    "        insertion_sort(data)\n",
    "        assert_equal(data, [])\n",
 </s> add     "        assert_equal(insertion_sort.sort([]), [])\n", </s> remove     "        data = []\n",
    "        insertion_sort(data)\n",
    "        assert_equal(data, [])\n",
 </s> add     "        assert_equal(insertion_sort.sort([]), [])\n",
    "        insertion_sort = InsertionSort()\n",
    "\n",
      "\n",
      "class TestInsertionSort(object):\n",
      "\n",
      "    def test_insertion_sort(self):\n",
    "        insertion_sort = InsertionSort()\n",
    "\n",
      "        print('None input')\n",
      "        assert_raises(TypeError, insertion_sort.sort, None)\n",
      "\n",
      "        print('Empty input')\n",
keep keep keep add keep keep keep keep
 Update insertion sort challenge (#129)

Update constraints, test cases, code, and tests. 
sorting_searching/insertion_sort/insertion_sort_challenge.ipynb