Issue #11286: Fixed unpickling of empty 2.x strings.
diff --git a/Lib/test/test_pickletools.py b/Lib/test/test_pickletools.py
index 823b0c2..d37ac26 100644
--- a/Lib/test/test_pickletools.py
+++ b/Lib/test/test_pickletools.py
@@ -9,8 +9,8 @@
     def dumps(self, arg, proto=None):
         return pickletools.optimize(pickle.dumps(arg, proto))
 
-    def loads(self, buf):
-        return pickle.loads(buf)
+    def loads(self, buf, **kwds):
+        return pickle.loads(buf, **kwds)
 
     # Test relies on precise output of dumps()
     test_pickle_to_2x = None