diff --git a/README.md b/README.md
index bcc989727b6..b2a5110b5bb 100644
--- a/README.md
+++ b/README.md
@@ -78,7 +78,7 @@ If you're using `DistributedDataParallel`, make the following changes:
 +import torch_xla.distributed.xla_multiprocessing as xmp
 +import torch_xla.distributed.xla_backend
 
- def _mp_fn(rank, world_size):
+ def _mp_fn(rank):
    ...
 
 -  os.environ['MASTER_ADDR'] = 'localhost'