code: def test_expand_hostlist(hostlist, expected):
      assert _expand_hostlist(hostlist) == expected.split(",")
  
imports: import os
  import pytest
  import torch
  import torch.distributed
  from ignite.distributed.comp_models import has_native_dist_support
label_desc: Use image node_id 1 for calling a global function with example usage: test_expand_hostlist(hostlist, expected) without return types