Remove unused imports in test modules.
diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
index db93db1..f125152 100755
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -149,7 +149,6 @@
 
 import cStringIO
 import getopt
-import itertools
 import json
 import os
 import random
@@ -448,8 +447,8 @@
 
     if use_mp:
         from threading import Thread
-        from Queue import Queue, Empty
-        from subprocess import Popen, PIPE, STDOUT
+        from Queue import Queue
+        from subprocess import Popen, PIPE
         from collections import deque
         debug_output_pat = re.compile(r"\[\d+ refs\]$")
         pending = deque()