--- a/mercurial/ancestor.py	Wed Aug 05 14:21:46 2015 -0400
+++ b/mercurial/ancestor.py	Fri Aug 07 19:45:48 2015 -0700
@@ -5,9 +5,12 @@
 # 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
+
 import collections
 import heapq
-from node import nullrev
+
+from .node import nullrev
 
 def commonancestorsheads(pfunc, *nodes):
     """Returns a set with the heads of all common ancestors of all nodes,