@classmethod
    def add_field(cls, field_cls):
        field_registry.register(field_cls)
        cls.field_classes.append(field_cls)
Unregister some listener; ignore if the listener was never
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/reviews/fields.py/BaseReviewRequestFieldSet.add_field--crossover with--dataset/ETHPy150Open ncclient/ncclient/ncclient/transport/session.py/Session.remove_listener