fix

Author: awaelchli

tests/tests_fabric/strategies/test_ddp.py

@@ -16,6 +16,7 @@
 
 import pytest
 import torch
+from torch.nn.parallel import DistributedDataParallel
 
 from lightning_fabric.strategies import DDPStrategy
 from lightning_fabric.strategies.ddp import _DDPBackwardSyncControl