Whoops. Adding the .parent attribute to the Serializer class broke

getattr(self,'parent',self). This fixes it.

djangorestframework/serializer.py

@@ -138,7 +138,7 @@ class Serializer(object):
         if isinstance(info, (list, tuple)):
             class OnTheFlySerializer(self.__class__):
                 fields = info
-                parent = getattr(self, 'parent', self)
+                parent = getattr(self, 'parent') or self
             return OnTheFlySerializer
 
         # If an element in `fields` is a 2-tuple of (str, Serializer)