code: def execute_work_items(work_items, config):
      
      return celery.group(
          worker_task.s(work_item, config)
          for work_item in work_items
      )
docs: Execute a suite of tests for a given set of work items.
  
      Args:
        work_items: An iterable of `work_db.WorkItem`s.
        config: The configuration to use for the test execution.
  
      Returns: An iterable of WorkItems.