JsonModel data_wrapper should default to false
diff --git a/apiclient/model.py b/apiclient/model.py
index 14ec397..9781b35 100644
--- a/apiclient/model.py
+++ b/apiclient/model.py
@@ -73,7 +73,7 @@
   object representation of HTTP request and response bodies.
   """
 
-  def __init__(self, data_wrapper):
+  def __init__(self, data_wrapper=False):
     """Construct a JsonModel
 
     Args: