Fix #8684: make sched.scheduler class thread-safe
diff --git a/Misc/NEWS b/Misc/NEWS
index bf7399d..a7a3506 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -409,6 +409,9 @@
 Library
 -------
 
+- Issue #8684 sched.scheduler class can be safely used in multi-threaded
+  environments.
+
 - Alias resource.error to OSError ala PEP 3151.
 
 - Issue #5689: Add support for lzma compression to the tarfile module.