fix a case of set_daemon #5087
diff --git a/Doc/library/queue.rst b/Doc/library/queue.rst
index e90f276..4ed3dcc 100644
--- a/Doc/library/queue.rst
+++ b/Doc/library/queue.rst
@@ -147,7 +147,7 @@
    q = Queue()
    for i in range(num_worker_threads):
         t = Thread(target=worker)
-        t.set_daemon(True)
+        t.daemon = True
         t.start()
 
    for item in source():