file -> open for 3.x support.  This fixes #152
diff --git a/jinja2/environment.py b/jinja2/environment.py
index d19ae15..ed59779 100644
--- a/jinja2/environment.py
+++ b/jinja2/environment.py
@@ -1069,7 +1069,7 @@
         """
         close = False
         if isinstance(fp, six.string_types):
-            fp = file(fp, 'w')
+            fp = open(fp, 'w')
             close = True
         try:
             if encoding is not None: