def mean_reduce_ddp_metrics(self, metrics: Dict) -> Dict:
        """Syncs ``metrics`` over ``world_size`` in the distributed mode."""
        metrics = {
            k: mean_reduce(
                torch.tensor(v, device=self.device),
                world_size=self.state.num_processes,
            )
            for k, v in metrics.items()
        }
        return metrics
Syncs ``metrics`` over ``world_size`` in the distributed mode.
catalyst/engines/torch.py