docstr: Tests that a placeholder in the graph is not DCE'd, as that would change
  the function signature.
docstr_tok: ["Tests","that","a","placeholder","in","the","graph","is","not","DCE","'d",",","as","that","would","change","the","function","signature","."]
code: def test_dead_placeholder(self):
      """
      Tests that a placeholder in the graph is not DCE'd, as that would change
      the function signature.
      """
  
      class TestModule(torch.nn.Module):
          def forward(self, x, y):
              return x + 7
  
      self._run_dce_and_test(TestModule(), expect_dce_changes=False)
  
file_path: pytorch/test/fx/test_dce_pass.py
imports: from typing import Set, Type
  import torch
  import torch.fx
  from torch.testing._internal.common_utils import TestCase
label_desc: Use image node_id 7 for calling the TestDCE obj's underlying member method code with example usage: obj.test_dead_placeholder() and returns: unknown