code: def test_post_autograd_returns_leaf(self, mode):
      with autograd_fallback_mode(mode):
          lib = self.get_lib()
          lib.define("foo(Tensor a) -> (Tensor, Tensor)")
          op = self.get_op("foo")
  
          lib.impl(
              "foo",
              lambda a: (
                  a.clone(),
                  a.clone().detach().requires_grad_(),
              ),
              "CPU",
          )
          x = torch.randn(3, requires_grad=True)
          y, z = op(x)
          with self._check_ctx(mode):
              z.sum().backward()
  
imports: import contextlib
  import warnings
  import numpy
  import torch
  from torch.library import Library
  from torch.testing._internal.common_utils import instantiate_parametrized_tests, parametrize, run_tests, TestCase
label_desc: Use image node_id 13 for calling the TestAutogradFallback obj's underlying member method code with example usage: obj.test_post_autograd_returns_leaf(mode) without return types