code: def test_list_artifacts_empty_hdfs_dir(hdfs_system_mock):
      hdfs_system_mock.return_value.exists.return_value = False
  
      repo = HdfsArtifactRepository("hdfs:/some_path/maybe/path")
      actual = repo.list_artifacts()
      assert actual == []
  
imports: import os
  import sys
  from io import BufferedReader
  from tempfile import NamedTemporaryFile
  from unittest import mock
  from unittest.mock import ANY, call, mock_open
  import pytest
  from pyarrow import HadoopFileSystem
  from mlflow.entities import FileInfo
  from mlflow.store.artifact.hdfs_artifact_repo import HdfsArtifactRepository, _download_hdfs_file, _parse_extra_conf, _relative_path_remote, _resolve_base_path
  from mlflow.utils.file_utils import TempDir
label_desc: Use image node_id 8 for calling a global function with example usage: test_list_artifacts_empty_hdfs_dir(hdfs_system_mock) without return types