Fix DDP notes (#111833)

malfet · pytorchmergebot · commit d22e5e4b5266 · 2023-10-23T22:05:36.000Z
To include `import os` otherwise sample is not syntactically correct Reported in pytorch/pytorch.github.io#1490 Pull Request resolved: #111833 Approved by: https://github.com/wanchaol
diff --git a/docs/source/notes/ddp.rst b/docs/source/notes/ddp.rst
@@ -28,6 +28,7 @@ updated, and all models on different processes should be exactly the same.
     import torch.multiprocessing as mp
     import torch.nn as nn
     import torch.optim as optim
+    import os
     from torch.nn.parallel import DistributedDataParallel as DDP
 
 
