Google App Engine: JSON module

I'm using JSON with Google App Engine.

I'm using JSON for comunication, so on the Python side I have:

import json

The error I'm getting is this:

<class 'django.core.exceptions.ViewDoesNotExist'>: Could not import views.ganttapp. Error was: No module named json

In my stand-alone this works great. Is there any problem with JSON on Google App Engine? Or should I use another module?

I don't know if you can open this, but here it goes: http://ganttapp.appspot.com/newgantt. You can find the error here.