我从请求中得到了下面的JSON响应。我知道如何使用JSON Extractor从响应中提取值，但这里我有不同的JSON响应，没有声明花括号，它从字符串开始OK。我尝试了JSON运算符，但没有得到任何结果。我想从这个响应中提取值14869。

OK
[
    [
        [
            14869,
            8708,
            5032,
            463863,
            "AssignmentCardLearning",
            "{\"type\": \"AssignmentCardRefreshDone\", \"value\": {\"byEducator\": true}}",
            "{\"openTime\": 1701326839556, \"finishTime\": 1701326994605, \"postponeData\": null, \"lastTimeOpened\": 1702469689831, \"lastTimeOpenedBy\": {\"type\": \"AssignmentCardOpenedByUser\", \"value\": {}}, \"availabilityDatesM\": null, \"previousFinishTime\": null}",
            "{\"tags\": [{\"type\": \"AssignmentCardGracePeriodNotified\", \"value\": {\"closed\": false}}], \"loIds\": [], \"language\": null, \"practiceSetLOs\": [], \"packageTopicsIds\": [5032]}",
            0,
            "2023-11-30 06:47:14",
            0,
            0,
            0
        ]
    ]
]

字符串