code: def test_set_keys(self):
      x = ModelOutputTest(a=30)
      x["a"] = 10
      self.assertEqual(x.a, 10)
      self.assertEqual(x["a"], 10)
  
imports: import unittest
  from dataclasses import dataclass
  from typing import Optional
  from transformers.testing_utils import require_torch
  from transformers.utils import ModelOutput
label_desc: Use image node_id 6 for calling the ModelOutputTester obj's underlying member method code with example usage: obj.test_set_keys() without return types