Python协程中使用上下文

obj_ref_dict obj-3: <A|x: 3> in obj_ref_dict obj-4: <A|x: 4> in obj_ref_dict obj-5: <A|x: 5> in obj_ref_dict obj in obj_ref_dict obj-3: None in obj_ref_dict obj-4: None in obj_ref_dict obj-5: None in obj_ref_dict obj