    def wrap_model(self, model: "Model") -> Tuple["Model", DdpWrappedModel]:
        """
        Wrap the AllenNLP `Model`, returning the original model (possibly on a different device)
        and the [wrapper model](#ddpwrappedmodel).
        """
        raise NotImplementedError
Wrap the AllenNLP `Model`, returning the original model (possibly on a different device)
and the [wrapper model](#ddpwrappedmodel).
allennlp/nn/parallel/ddp_accelerator.py