code: def test_all_reduce_coalesced(self):
      t0 = torch.ones(3, 3) * dist.get_rank()
      t1 = torch.ones(3, 3) * dist.get_rank() * 2
      dist.all_reduce_coalesced([t0, t1])
      res_num = ((0 + self.world_size - 1) * self.world_size) / 2
      self.assertEqual(t0, torch.ones(3, 3) * res_num)
      self.assertEqual(t1, torch.ones(3, 3) * (res_num * 2))
  
imports: import os
  import sys
  import torch
  import torch.distributed
  from torch._C._distributed_c10d import ReduceOp
  from unittest import skip, SkipTest
  import operator
  from functools import reduce
  import threading
  import torch.autograd
  from torch.testing._internal.common_distributed import spawn_threads_and_init_comms, MultiThreadedTestCase, skip_if_lt_x_gpu
  from torch.testing._internal.common_utils import TestCase, run_tests, IS_SANDCASTLE
label_desc: Use image node_id 16 for calling the TestCollectivesWithBaseClass obj's underlying member method code with example usage: obj.test_all_reduce_coalesced() without return types