Remove a dead import line.

brettcannon · brettcannon · commit 6f1057605b26 · 2013-06-14T10:42:48.000-04:00
Noticed by Serhly Storchaka.
diff --git a/Lib/test/test_pep352.py b/Lib/test/test_pep352.py
@@ -1,7 +1,6 @@
 import unittest
 import builtins
 import warnings
-from test.support import run_unittest
 import os
 from platform import system as platform_system
 
