how to make serializers work with db.Model

[Coonay]

Background: code on google app engine using django framework,

i persist data into google data store(which is not a dbms),there is
an error of "django AttributeError: object has no attribute
'_meta'" when reading the queryset and decoding the queryset using
djago json serializers.

As you know , the appengine_helper_for_django project can fit this
gap ,but its performance is very disappointed ,which always take near
1 second to finish its job.so there are 3 options :
1:optimize the helper(but it seems that project is not kind of active)
2:patch the django serializers
3:search a existed module which take cpu time blow 200MS

At present ,i prefer the option 2 and option 3,but i need your help to
get started .thanks you so much