code: def test_outputs(self):
      # Test that the outputs parameter is optional and is a sequence of FormalParameter tuples
      outputs = [
          defs.OpSchema.FormalParameter(
              name="output1",
              type_str="T",
              description="The first output.",
          )
      ]
  
      schema = defs.OpSchema(
          "test_op",
          "test_domain",
          1,
          outputs=outputs,
          type_constraints=[("T", ["tensor(int64)"], "")],
      )
      self.assertEqual(len(schema.outputs), 1)
      self.assertEqual(schema.outputs[0].name, "output1")
      self.assertEqual(schema.outputs[0].type_str, "T")
      self.assertEqual(
          schema.outputs[0].description, "The first output."
      )
  
imports: import unittest
  from typing import Sequence
  import parameterized
  import onnx
  from onnx import defs
label_desc: Use image node_id 10 for calling the TestOpSchema obj's underlying member method code with example usage: obj.test_outputs() without return types