code: def test_user_metadata_not_dict(workflow_start_regular):
      @ray.remote
      def simple():
          return 0
  
      with pytest.raises(ValueError):
          workflow.run_async(
              simple.options(**workflow.options(metadata="x")).bind()
          )
  
      with pytest.raises(ValueError):
          workflow.run(simple.bind(), metadata="x")
  
file_path: ray/python/ray/workflow/tests/test_metadata.py
imports: import time
  from ray.tests.conftest import *
  import pytest
  import ray
  from ray import workflow
label_desc: Use image node_id 3 for calling a global function with example usage: test_user_metadata_not_dict(workflow_start_regular) and returns: int