Repair KeyError when running test_threaded_import under -R,

as reported by Neal on python-dev.

Lib/test/test_threaded_import.py

@@ -30,11 +30,10 @@ def test_import_hangers():
     if verbose:
         print "testing import hangers ...",
 
-    from test import threaded_import_hangers
-
+    import test.threaded_import_hangers
     try:
-        if threaded_import_hangers.errors:
-            raise TestFailed(threaded_import_hangers.errors)
+        if test.threaded_import_hangers.errors:
+            raise TestFailed(test.threaded_import_hangers.errors)
         elif verbose:
             print "OK."
     finally: