code: def test_torch_fsdp_ckpt():
      spawn(run_dist, 2)
  
file_path: ColossalAI/tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py
imports: import pytest
  import torch
  from packaging import version
  from torch.optim import SGD
  from torchvision.models import resnet18
  from utils import shared_tempdir
  import colossalai
  from colossalai.booster import Booster
  from colossalai.testing import rerun_if_address_is_in_use, spawn
label_desc: Use image node_id 4 for calling a global function with example usage: test_torch_fsdp_ckpt() without return types