Add weakref support to the thread.lock type.
diff --git a/Misc/NEWS b/Misc/NEWS
index 8977e19..7bb0d5e 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -359,6 +359,8 @@
 Library
 -------
 
+- The thread.lock type now supports weak references.
+
 - Issue #1356969: Add missing info methods in Tix.HList.
 
 - Issue #1522587: New constants and methods for the Tix.Grid widget.