diff --git a/src/test/py/test_logical_operations.py b/src/test/py/test_logical_operations.py
index 0eda349..a66258a 100644
--- a/src/test/py/test_logical_operations.py
+++ b/src/test/py/test_logical_operations.py
@@ -12,10 +12,10 @@ class calculationsWithRoots(unittest.TestCase):
     def test_disconjunctive_identity_1_and_0_equals_x(self):
         self.assertEqual(identity_conjunctive(1, 0), 1)
 
-    def test_disconjunctive_identity_1_and_1_equals_NULL(self):
+    def test_disconjunctive_identity_1_and_1_equals_None(self):
         self.assertEqual(identity_conjunctive(1, 1), None)
 
-    def test_disconjunctive_identity_1_and_1_equals_NULL(self):
+    def test_disconjunctive_identity__and_1_equals_None(self):
         self.assertEqual(identity_conjunctive(0, 1), None)