  
  class TestInsertionSort(object):
  
      def test_insertion_sort(self):
          print('Empty input')
          data = []
          insertion_sort(data)
          assert_equal(data, [])
 
</s> remove     "    if len(data) < 2:\n",
 </s> add     "    if data is None or len(data) < 2:\n", </s> remove    "pygments_lexer": "ipython2",
   "version": "2.7.10"
 </s> add    "pygments_lexer": "ipython3",
   "version": "3.4.3" </s> remove     "version": 2
 </s> add     "version": 3
        print('None input')
        data = None
        insertion_sort(data)
        assert_equal(data, None)

  
  class TestInsertionSort(object):
  
      def test_insertion_sort(self):
        print('None input')
        data = None
        insertion_sort(data)
        assert_equal(data, None)

          print('Empty input')
          data = []
          insertion_sort(data)
          assert_equal(data, [])
keep keep keep add keep keep keep keep
 Add None input test case to insertion sort 
sorting_searching/insertion_sort/test_insertion_sort.py