diff -r bbcbb82e3589 -r 66f2cc210a29 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Sun Oct 06 14:51:45 2019 -0400
+++ b/mercurial/cmdutil.py	Sun Oct 06 14:58:42 2019 -0400
@@ -19,7 +19,10 @@
     nullrev,
     short,
 )
-from .pycompat import open
+from .pycompat import (
+    open,
+    setattr,
+)
 
 from . import (
     bookmarks,