code: def stderr(self) -> Iterator[str]:
      assert self.process.stderr is not None
      return (line.decode() for line in self.process.stderr)
  
file_path: determined/e2e_tests/tests/command/command.py
imports: import os
  import re
  import subprocess
  from contextlib import contextmanager
  from typing import IO, Any, Iterator, Optional
  import requests
  from determined.common import api
  from determined.common.api import authentication, certs, task_logs
  from tests import api_utils
  from tests import config
label_desc: Use image node_id 3 for calling the _InteractiveCommandProcess obj's underlying member method code with example usage: obj.stderr() and returns: unknown