code: def register(workflow_id, workflow_version):
      
      name = "workflow_definitions:{}:{}".format(workflow_id, workflow_version)
      workflow_definition = dict(id=workflow_id, version=workflow_version,
                                 stages=[])
      # DB.set_hash_values(name, workflow_definition)
      DB.save_dict(name, workflow_definition, hierarchical=False)
docs: Register an (empty) workflow definition in the database.