Used by Variable/Connection.

https://github.com/apache/airflow/blob/894741e311ffd642e036b80d3b1b5d53c3747cad/airflow/secrets/metastore.py#L32

elif k == "timetable":
                v = _decode_timetable(v)
            elif k in cls._decorated_fields:
                v = cls.deserialize(v)
            elif k == "params":
                v = cls._deserialize_params_dict(v)
            elif k == "dataset_triggers":
                v = cls.deserialize(v)
            
            setattr(dag, k, v)
        
        
        
        if "timetable" in encoded_dag:
            dag.schedule_interval = dag.timetable.summary
        else:
            dag.timetable = create_timetable(dag.schedule_interval, dag.timezone)
        
        if "_task_group" in encoded_dag:
            dag._task_group = TaskGroupSerialization.deserialize_task_group(
                encoded_dag["_task_group"],
                None,
                dag.task_dict,
                dag,
            )
        else:
            
            
            dag._task_group = TaskGroup.create_root(dag)
            for task in dag.tasks: