diff --git a/DDG4/python/g4units.py b/DDG4/python/g4units.py
index 894a8048da69939983d41f5f84910e944aa8f0cf..2d348d46b8c41023e21439051864fdd14155e200 100644
--- a/DDG4/python/g4units.py
+++ b/DDG4/python/g4units.py
@@ -48,6 +48,8 @@
 #
 # Length [L]
 #
+from __future__ import absolute_import, unicode_literals, division
+
 millimeter  = 1.
 millimeter2 = millimeter*millimeter
 millimeter3 = millimeter*millimeter*millimeter