diff --git a/test_maya.py b/test_maya.py
index 31deaaa..036c408 100644
--- a/test_maya.py
+++ b/test_maya.py
@@ -86,7 +86,7 @@ def test_format():
     d = maya.parse('01/05/2016')
     assert format(d) == '2016-01-05 00:00:00+00:00'
 
-    d = maya.parse('01/05/2016', dayfirst=True)
+    d = maya.parse('01/05/2016', day_first=True)
     assert format(d) == '2016-05-01 00:00:00+00:00'
 
 # rand_day = maya.when('2011-02-07', timezone='US/Eastern')