Issue #23921: Standardized documentation whitespace formatting.
Original patch by James Edwards.
diff --git a/Doc/library/threading.rst b/Doc/library/threading.rst
index ccb922b..e16f78c 100644
--- a/Doc/library/threading.rst
+++ b/Doc/library/threading.rst
@@ -778,7 +778,7 @@
        print "hello, world"
 
    t = Timer(30.0, hello)
-   t.start() # after 30 seconds, "hello, world" will be printed
+   t.start()  # after 30 seconds, "hello, world" will be printed
 
 
 .. class:: Timer(interval, function, args=[], kwargs={})