Fix the with_poll tests for platforms without poll.  missing import.
diff --git a/Lib/test/test_telnetlib.py b/Lib/test/test_telnetlib.py
index c66f49b..7fdb49e 100644
--- a/Lib/test/test_telnetlib.py
+++ b/Lib/test/test_telnetlib.py
@@ -3,6 +3,7 @@
 import time
 import Queue
 
+import unittest
 from unittest import TestCase
 from test import test_support
 threading = test_support.import_module('threading')