Different name for builtins in Python 3

--HG--
branch : trunk
diff --git a/jinja2/utils.py b/jinja2/utils.py
index 8bf2c7f..0db4653 100644
--- a/jinja2/utils.py
+++ b/jinja2/utils.py
@@ -236,7 +236,8 @@
         return 'None'
     elif obj is Ellipsis:
         return 'Ellipsis'
-    if obj.__class__.__module__ == '__builtin__':
+    # __builtin__ in 2.x, builtins in 3.x
+    if obj.__class__.__module__ in ('__builtin__', 'builtins'):
         name = obj.__class__.__name__
     else:
         name = obj.__class__.__module__ + '.' + obj.__class__.__name__