Index: Lib/_threading_local.py
===================================================================
--- Lib/_threading_local.py	(revision 60205)
+++ Lib/_threading_local.py	(working copy)
@@ -187,30 +187,21 @@
 
     def __getattribute__(self, name):
         lock = object.__getattribute__(self, '_local__lock')
-        lock.acquire()
-        try:
+        with lock:
             _patch(self)
             return object.__getattribute__(self, name)
-        finally:
-            lock.release()
 
     def __setattr__(self, name, value):
         lock = object.__getattribute__(self, '_local__lock')
-        lock.acquire()
-        try:
+        with lock:
             _patch(self)
             return object.__setattr__(self, name, value)
-        finally:
-            lock.release()
 
     def __delattr__(self, name):
         lock = object.__getattribute__(self, '_local__lock')
-        lock.acquire()
-        try:
+        with lock:
             _patch(self)
             return object.__delattr__(self, name)
-        finally:
-            lock.release()
 
     def __del__(self):
         import threading