code: def test_device_mesh_hash(self):
      mesh_tensor_2d = torch.arange(8).reshape(4, 2)
      mesh = DeviceMesh(self.device_type, mesh_tensor_2d)
      mesh2 = DeviceMesh(self.device_type, mesh_tensor_2d)
      self.assertNotEqual(hash(mesh), hash(mesh2))
      mesh_tensor_3d = torch.arange(8).reshape(2, 2, 2)
      mesh3 = DeviceMesh(self.device_type, mesh_tensor_3d)
      self.assertNotEqual(hash(mesh), hash(mesh3))
      self.assertNotEqual(hash(mesh2), hash(mesh3))
  
imports: import os
  import torch
  import torch.distributed._functional_collectives
  from torch.distributed._tensor import DTensor
  from torch.distributed._tensor._collective_utils import mesh_all_to_all, mesh_broadcast, mesh_scatter
  from torch.distributed._tensor.placement_types import _Partial, Shard
  from torch.distributed.device_mesh import _mesh_resources, DeviceMesh, init_device_mesh
  from torch.distributed.distributed_c10d import get_global_rank, get_world_size, init_process_group, is_initialized, is_nccl_available, ProcessGroup
  from torch.testing._internal.common_utils import run_tests
  from torch.testing._internal.distributed._tensor.common_dtensor import DTensorTestBase, with_comms
  from torch.testing._internal.distributed.fake_pg import FakeStore
label_desc: Use image node_id 3 for calling the DeviceMeshTestNDim obj's underlying member method code with example usage: obj.test_device_mesh_hash() without return types