Add threading.get_ident to whatsnew.

Doc/whatsnew/3.3.rst

@@ -1911,6 +1911,12 @@ The :class:`threading.Thread` constructor now accepts a ``daemon`` keyword
 argument to override the default behavior of inheriting the ``deamon`` flag
 value from the parent thread (:issue:`6064`).
 
+The formerly private function ``_thread.get_ident`` is now available as the
+public function :func:`~threading.get_ident`.  This eliminates several cases of
+direct access to the ``_thread`` module in the stdlib.  Third party code that
+used ``_thread.get_ident`` should likewise be changed to use the new public
+interface.
+
 
 time
 ----