code: def test_is(self) -> None:
      self.assertTrue(self.ok.is_ok())
      self.assertFalse(self.ok.is_err())
  
      self.assertFalse(self.err.is_ok())
      self.assertTrue(self.err.is_err())
  
file_path: Ax/ax/utils/common/tests/test_result.py
imports: from ax.utils.common.result import Err, Ok, Result, UnwrapError
  from ax.utils.common.testutils import TestCase
label_desc: Use image node_id 4 for calling the ResultTest obj's underlying member method code with example usage: obj.test_is() without return types