title: How to return a key if the value equal to specific value using jq in json parsing
body: <p>I have json file like this</p>
  <pre><code>{
    &quot;version&quot;: &quot;4.6.0&quot;,
    &quot;flags&quot;: {
      &quot;T1&quot;: true,
      &quot;T1c&quot;: false,
      &quot;T2&quot;: false,
      &quot;FLAIR&quot;: false
    },
    &quot;shapes&quot;: [],
    &quot;imagePath&quot;: &quot;HC-002_LM-0000_aparc+aseg_1mm_bin.png&quot;,
    &quot;imageData&quot;:xxxxxxxxx
  }
  </code></pre>
  <p>and I need the output to be</p>
  <pre><code>T1
  </code></pre>
  <p>as the value is true, Please suggest correct use of jq here, thanks!</p>