--- a/mercurial/patch.py	Mon May 18 11:36:33 2015 -0400
+++ b/mercurial/patch.py	Sun May 17 17:27:10 2015 -0700
@@ -16,7 +16,6 @@
 
 from i18n import _
 from node import hex, short
-import cStringIO
 import base85, mdiff, scmutil, util, diffhelpers, copies, encoding, error
 import pathutil