Improve threading.daemon docstring (GH-14278)

Rephrase and clarify that "the entire Python program exits when only daemon threads are left". This matches the documentation at https://docs.python.org/3/library/threading.html#thread-objects.

diff --git a/Lib/threading.py b/Lib/threading.py
index 01a15a6fc075ac1ce619c4bc75fb61b1700fd474..cec9cdb8e6985fc505e1900131cb28e02ed35399 100644 (file)
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -1107,8 +1107,7 @@ class Thread:
         main thread is not a daemon thread and therefore all threads created in
         the main thread default to daemon = False.
 
-        The entire Python program exits when no alive non-daemon threads are
-        left.
+        The entire Python program exits when only daemon threads are left.
 
         """
         assert self._initialized, "Thread.__init__() not called"