@base.resource(Attachments)
    def attachments(self):
        return Attachments(self)
Removes null property values because they aren't valid in Neo4j.
dataset/ETHPy150Open ducksboard/libsaas/libsaas/services/trello/cards.py/Card.attachments--crossover with--dataset/ETHPy150Open espeed/bulbs/bulbs/rexster/client.py/RexsterClient._remove_null_values