diff -r 849826a900d2 Lib/test/test_threading.py
--- a/Lib/test/test_threading.py	Tue Oct 25 21:49:19 2016 -0500
+++ b/Lib/test/test_threading.py	Fri Oct 28 09:22:14 2016 +0200
@@ -462,7 +462,7 @@
         self.addCleanup(sys.setswitchinterval, old_interval)
 
         # Make the bug more likely to manifest.
-        sys.setswitchinterval(1e-6)
+        test.support.setswitchinterval(1e-6)
 
         for i in range(20):
             t = threading.Thread(target=lambda: None)