def __call__(self, *funcObjs):
        if not funcObjs:
            raise TypeError("expose() takes at least 1 argument (0 given)")
        for fObj in funcObjs:
            fObj.exposedThrough = getattr(fObj, 'exposedThrough', [])
            fObj.exposedThrough.append(self)
        return funcObjs[0]
Subscription create adds a new subscription.
dataset/ETHPy150Open twisted/nevow/nevow/util.py/Expose.__call__--crossover with--dataset/ETHPy150Open nickjj/build-a-saas-app-with-flask/catwatch/tests/billing/test_views.py/TestBilling.test_subscription_update