Api_get_group_announcements_output(get_group_announcements 响应数据)

{
    "announcements": [
        {
            "group_id": -9007199254740991,
            "announcement_id": "string",
            "user_id": -9007199254740991,
            "time": -9007199254740991,
            "content": "string",
            "image_url": "string"
        }
    ]
}