let dateList = [ "2019-07-22T08:40:33.537Z", "2019-07-22T08:40:33.537Z", "2019-07-23T12:02:53.143Z", "2019-07-23T12:02:53.143Z", "2019-07-23T12:12:00.434Z", "2019-07-23T12:12:54.649Z", "2019-07-23T12:14:57.547Z", "2019-07-23T12:14:57.547Z", "2019-07-23T12:16:45.011Z", "2019-07-23T12:16:45.011Z", "2019-07-23T12:21:20.527Z", "2019-07-23T12:24:30.095Z", "2019-07-23T12:25:33.251Z", "2019-07-23T12:27:53.809Z", "2019-07-23T12:27:53.809Z" ]

let uniqueDates = [...new Set(dateList)];