How to yo set up the DistributedDataparallel for evaluation?
 self.model = EfficientDet(num_classes=args.num_class,
                         network=args.network,
                         W_bifpn=EFFICIENTDET[args.network]['W_bifpn'],
                         D_bifpn=EFFICIENTDET[args.network]['D_bifpn'],
                         D_class=EFFICIENTDET[args.network]['D_class']
                         )

        #self.model = torch.nn.parallel.DistributedDataParallel(self.model, device_ids=[args.gpu],find_unused_parameters=True)
        #self.model =  torch.nn.parallel.DistributedDataParallel(self.model)
        self.model = torch.nn.parallel.DistributedDataParallel(
            self.model, output_device=[1])