diff -r 414a3513c2bd -r a8994d08e4a2 mercurial/templater.py
--- a/mercurial/templater.py	Sun Sep 03 15:47:17 2017 +0900
+++ b/mercurial/templater.py	Sun Sep 03 14:56:31 2017 +0900
@@ -5,7 +5,7 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
-from __future__ import absolute_import
+from __future__ import absolute_import, print_function
 
 import os
 import re
@@ -192,7 +192,7 @@
     """Expand list of templates to node tuple
 
     >>> def f(tree):
-    ...     print prettyformat(_unnesttemplatelist(tree))
+    ...     print(pycompat.sysstr(prettyformat(_unnesttemplatelist(tree))))
     >>> f((b'template', []))
     (string '')
     >>> f((b'template', [(b'string', b'foo')]))