code: def spawn_and_init(fn, args=None, **spawn_kwargs):
      if args is None:
          args = ()
      run_fn = functools.partial(init_and_run, fn, args)
      spawn_for_all_world_sizes(run_fn, **spawn_kwargs)
  
file_path: fairscale/tests/utils/test_reduce_scatter_bucketer.py
imports: import functools
  import itertools
  import sys
  import unittest
  from unittest import mock
  from parameterized import parameterized
  import torch
  from fairscale.fair_dev.testing.testing import dist_init, spawn_for_all_world_sizes
  from fairscale.internal import torch_version
  from fairscale.internal.reduce_scatter_bucketer import ReduceScatterBucketer
label_desc: Use image node_id 2 for calling a global function with example usage: spawn_and_init(fn, args) without return types