def serialize(self, content_type, link, state):
        raise NotImplementedError
Retrieve the "sum" result of the query
dataset/ETHPy150Open zbyte64/django-hyperadmin/hyperadmin/mediatypes/common.py/MediaType.serialize--crossover with--dataset/ETHPy150Open sdispater/orator/orator/query/builder.py/QueryBuilder.sum