code: def test_docker_image_exists(
      test_settings,
      live_mock_server,
      mocked_fetchable_git_repo,
      monkeypatch,
  ):
      def raise_docker_error(args):
          raise DockerError(args, 1, b"", b"")
  
      monkeypatch.setattr(
          wandb.docker, "run", lambda args: raise_docker_error(args)
      )
      assert docker_image_exists("test:image") == False
  
file_path: wandb/tests/pytest_tests/unit_tests_old/test_launch/test_launch_docker.py
imports: from unittest.mock import MagicMock, mock_open, patch
  import wandb
  from wandb.docker import DockerError
  from wandb.sdk.launch._project_spec import EntryPoint, create_project_from_spec, fetch_and_validate_project
  from wandb.sdk.launch.builder.build import generate_dockerfile, get_base_setup
  from wandb.sdk.launch.utils import docker_image_exists
  from .test_launch import mocked_fetchable_git_repo, mocked_fetchable_git_repo_conda, mocked_fetchable_git_repo_nodeps
label_desc: Use image node_id 7 for calling a global function with example usage: test_docker_image_exists(test_settings, live_mock_server, mocked_fetchable_git_repo, monkeypatch) without return types