Thrift missing python threading import


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@664813 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/py/src/server/TServer.py b/lib/py/src/server/TServer.py
index 53260b8..eb2ec70 100644
--- a/lib/py/src/server/TServer.py
+++ b/lib/py/src/server/TServer.py
@@ -1,5 +1,6 @@
 import sys
 import traceback
+import threading
 
 from thrift.Thrift import TProcessor
 from thrift.transport import TTransport