state.
setstate(state)
  Takes a provided "state" and retrieves "PowerSGDState".
  "process_group" is set to default.

Here is a simple, end-to-end example of saving and reloading PowerSGD
state and hook.
import os
   import sys
   import tempfile
   import torch
   import torch.distributed as dist
   import torch.nn as nn
   import torch.optim as optim
from torch.distributed.algorithms.ddp_comm_hooks import powerSGD_hook as powerSGD
class SimpleModel(nn.Module):
       def init(self):
           super(SimpleModel, self).init()
           self.fc1 = nn.Linear(24,24)
           self.relu = nn.ReLU()
           self.fc2 = nn.Linear(24,12)
   def forward(self, x):
       return self.fc2(self.relu(self.fc1(x)))

def setup(rank, world_size):
       os.environ['MASTER_ADDR'] = 'localhost'
       os.environ['MASTER_PORT'] = '12355'
   # initialize the process group
   dist.init_process_group("nccl", rank=rank, world_size=world_size)

def cleanup():