readings.json

{
    "data": [
        {
            "datetime": "2016-10-01 00:15:00+02:00",
            "feed-in": 0,
            "reading": 5073078,
            "usage": 56
        },
        {
            "datetime": "2016-10-01 00:30:00+02:00",
            "feed-in": 0,
            "reading": 5073125,
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        },
        {
            "datetime": "2016-10-01 00:45:00+02:00",
            "feed-in": 0,
            "reading": 5073174,
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        },
        {
            "datetime": "2016-10-01 01:00:00+02:00",
            "feed-in": 0,
            "reading": 5073225,
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        }
      ]
}