code: def test_no_grad_in_hook(self):
      test_model = ModelForTest()
      x = torch.randn(2, 3)
      output = test_model(x)
  
      test_hook = PostForwardHook()
      add_hook_to_module(test_model, test_hook)
      output1 = test_model(x)
      self.assertTrue(torch.allclose(output1, output + 1))
      self.assertTrue(output1.requires_grad)
  
      test_hook.no_grad = True
      output1 = test_model(x)
      self.assertFalse(output1.requires_grad)
  
imports: import inspect
  import unittest
  import torch
  import torch.nn
  from accelerate.hooks import AlignDevicesHook, ModelHook, SequentialHook, add_hook_to_module, attach_align_device_hook, remove_hook_from_module, remove_hook_from_submodules
  from accelerate.test_utils import require_multi_gpu
label_desc: Use image node_id 5 for calling the HooksModelTester obj's underlying member method code with example usage: obj.test_no_grad_in_hook() without return types