Get rid of the remaining versionadded/versionchanged directives.
diff --git a/Doc/library/constants.rst b/Doc/library/constants.rst
index fecd836..8f7be50 100644
--- a/Doc/library/constants.rst
+++ b/Doc/library/constants.rst
@@ -5,19 +5,17 @@
 A small number of constants live in the built-in namespace.  They are:
 
 
+.. XXX False, True, None are keywords too
+
 .. data:: False
 
    The false value of the :class:`bool` type.
 
-   .. versionadded:: 2.3
-
 
 .. data:: True
 
    The true value of the :class:`bool` type.
 
-   .. versionadded:: 2.3
-
 
 .. data:: None