diff -aur -bZwB -x .git cadabra2-git.old/core/cadabra2 cadabra2-git/core/cadabra2
--- cadabra2-git.old/core/cadabra2	2016-03-08 06:55:56.245442657 -0500
+++ cadabra2-git/core/cadabra2	2016-03-08 06:56:27.278519443 -0500
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 #
 # \ingroup pythoncore
 #