code: def test_doc(self):
      schema = defs.OpSchema(
          "test_op", "test_domain", 1, doc="test_doc"
      )
      self.assertEqual(schema.doc, "test_doc")
  
imports: import unittest
  from typing import Sequence
  import parameterized
  import onnx
  from onnx import defs
label_desc: Use image node_id 8 for calling the TestOpSchema obj's underlying member method code with example usage: obj.test_doc() without return types