Add missing comma.

diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 4d3216b3df2b7043157c6be47073852166a3656f..72a3a7b51a523230049b2488c828c48cea3ddd6e 100644 (file)
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -1271,7 +1271,7 @@ Test cases
    .. method:: assertListEqual(first, second, msg=None)
                assertTupleEqual(first, second, 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