Good spot!
But now it hangs on both =/, editted above
$ python3 /home/dario/.local/lib/python3.6/site-packages/torch/distributed/launch.py --nnode=2 --node_rank=0 --nproc_per_node=1 msg3d/MSG3D/tuturial_DistributedDataParallel.py --local_world_size=1
[23616] Initializing process group with: {'MASTER_ADDR': '148.251.86.243', 'MASTER_PORT': '29500', 'RANK': '0', 'WORLD_SIZE': '2'}