code: def test_invoke_make_bw(self):
      x = torch.tensor([0.5, 0.5], requires_grad=True)
  
      def fwd(x):
          z = x * x
          return z + z
  
      res = fwd(x)
      res.backward(torch.tensor([1.0, 1.0]))
      out = make_fx(_multiply_invoke)(x.grad)
      self.assertEqual(out(x.grad), torch.tensor([4.0, 4.0]))
      actual = normalize_gm(out.print_readable(False))
  
      expected = """\
  class _multiply_invoke(torch.nn.Module):
      def forward(self, grad_1: "f32[2]"):
          trace_wrapped: "f32[2]" = torch__dynamo__trace_wrapped_higher_order_op_self_invoke(grad_1);  grad_1 = None
          assert_1: "f32[2]" = torch__dynamo__trace_wrapped_higher_order_op__assert_meta(trace_wrapped, (2,), (1,), torch.float32);  trace_wrapped = None
          return assert_1
  """
      self.assertExpectedInline(actual, expected)
  
imports: import functools
  import torch
  import torch._dynamo.test_case
  import torch._dynamo.testing
  import torch._dynamo.utils
  from torch import _inductor
  from torch._dynamo import compiled_autograd
  from torch._dynamo._trace_wrapped_higher_order_op import trace_wrapped
  from torch._dynamo.testing import normalize_gm
  from torch._dynamo.utils import counters
  from torch.fx.experimental.proxy_tensor import make_fx
label_desc: Use image node_id 4 for calling the BackwardHigherOrderOpTests obj's underlying member method code with example usage: obj.test_invoke_make_bw() and returns: unknown