title: React loop over an object with array
body: <pre><code>data = [
    {
      "2017-08-09": [
        "09:00",
        "09:30",
        "10:00",
        "10:30",
        "11:00",
        "11:30",
        "13:00",
        "13:30",
        "14:00",
        "14:30",
        "15:00",
        "15:30",
        "16:00",
        "16:30"
      ]
    }
  ]
  </code></pre>
  
  <p>I'm trying to map over this array of objects and display info as follows: </p>
  
  <pre><code>Date 2017-08-09 
  available hours 
    09:00
    09:30
    10:00
         ...
  </code></pre>
  
  <p>I'm having trouble looping over this data structure, </p>
  
  <p><a href="https://codesandbox.io/s/qzrvlvx9nj" rel="nofollow noreferrer">https://codesandbox.io/s/qzrvlvx9nj</a></p>