code: def test_fails_on_unknown_command(self):
      sys.argv = [
          "bogus",  # command
          "unknown_model",  # model_name
          "bogus file",  # input_file
          "--output-file",
          "bogus out file",
          "--silent",
      ]
  
      with pytest.raises(SystemExit) as cm:
          main()
  
      assert cm.value.code == 2
  
file_path: allennlp/tests/commands/main_test.py
imports: import shutil
  import sys
  import pytest
  from allennlp.commands import main
  from allennlp.commands.subcommand import Subcommand
  from allennlp.common.checks import ConfigurationError
  from allennlp.common.plugins import discover_plugins
  from allennlp.common.testing import AllenNlpTestCase
  from allennlp.common.util import push_python_path, pushd
label_desc: Use image node_id 1 for calling the TestMain obj's underlying member method code with example usage: obj.test_fails_on_unknown_command() without return types