code: def sample_empty_viewer_config():
      return {
          "@jupyterlab/docmanager-extension:plugin": {
              "defaultViewers": {}
          }
      }
  
file_path: jupytext/tests/unit/test_labconfig.py
imports: import json
  import pytest
  from jupytext_config.labconfig import LabConfig
label_desc: Use image node_id 2 for calling a global function with example usage: sample_empty_viewer_config() and returns: dict