Add missing comma.

diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 32d319fbe17c188fd70dba3e197dbc8c43e89e47..0a3f64b36a6f9f51dbbc5ca173f068e1cceab89b 100644 (file)
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -1157,7 +1157,7 @@ Test cases
    .. method:: assertListEqual(list1, list2, msg=None)
                assertTupleEqual(tuple1, tuple2, msg=None)
 
-      Tests that two lists or tuples are equal.  If not an error message is
+      Tests that two lists or tuples are equal.  If not, an error message is
       constructed that shows only the differences between the two.  An error
       is also raised if either of the parameters are of the wrong type.
       These methods are used by default when comparing lists or tuples with