Fix last traces of old threading API.
diff --git a/Doc/includes/mp_distributing.py b/Doc/includes/mp_distributing.py
index 24ae8f8..5cd12bb 100644
--- a/Doc/includes/mp_distributing.py
+++ b/Doc/includes/mp_distributing.py
@@ -243,7 +243,7 @@
         try:
             self.queue.clear()
             self.queue.extend(contents)
-            self.not_empty.notifyAll()
+            self.not_empty.notify_all()
         finally:
             self.not_empty.release()