diff --git a/tutorial.py b/tutorial.py
index 04e2fbb..945434c 100644
--- a/tutorial.py
+++ b/tutorial.py
@@ -178,7 +178,7 @@ class GalateaTutorial(ModelSQL, ModelView):
         value = None
         try:
             with open(filename, 'rb') as file_p:
-                value = buffer(file_p.read())
+                value = fields.Binary.cast(file_p.read())
         except IOError:
             pass
         return value