code: def test_nullprogress(self, mock_stderr) -> None:
      count = 0
      with NullProgress(["x", "y", "z"]) as np:
          for _ in np:
              for _ in NullProgress([1, 2, 3]):
                  count += 1
  
      self.assertEqual(count, 9)
      output = mock_stderr.getvalue()
      self.assertEqual(output, "")
  
file_path: captum/tests/utils/test_progress.py
imports: import io
  import unittest
  import unittest.mock
  from captum._utils.progress import NullProgress, progress
  from tests.helpers.basic import BaseTest
label_desc: Use image node_id 1 for calling the Test obj's underlying member method code with example usage: obj.test_nullprogress(mock_stderr) without return types