def METHOD_NAME(self):
    # Two similar cubes on identical but different meshes.
    cube1 = sample_mesh_cube()
    cube2 = sample_mesh_cube()
    self.assertEqual(cube1.mesh, cube2.mesh)
    self.assertIsNot(cube1.mesh, cube2.mesh)
    result = cube1 + cube2
    self.assertEqual(result.shape, cube1.shape)
    self.assertEqual(result.mesh, cube1.mesh)
    self.assertTrue(result.mesh is cube1.mesh or result.mesh is cube2.mesh)