def db_for_read(self, model, **hints):
        if model._meta.app_label == 'auth':
            # We use default here to ensure we can tell the difference
            # between a read request and a write request for Auth objects
            return 'default'
        return None
Update header information for extra fields.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/tests/regressiontests/multiple_database/tests.py/AuthRouter.db_for_read--crossover with--dataset/ETHPy150Open arq5x/gemini/gemini/gemini_load_chunk.py/GeminiLoader._update_extra_headers