Python 3 support
diff --git a/predictionio/connection.py b/predictionio/connection.py
index 9609047..2c79d64 100644
--- a/predictionio/connection.py
+++ b/predictionio/connection.py
@@ -153,7 +153,7 @@
     # Try to extract the json.
     try:
       self.json_body = json.loads(body)
-    except ValueError, ex:
+    except ValueError as ex:
       self.json_body = None
 
   def set_error(self, error):