title: dart freezed convert to another data type
body: <p><code>@JsonKey(name: &quot;favourite&quot;) @Default(&quot;&quot;) String favourite</code></p>
  <p>In my json <code>favourite</code> is rather <code>Y</code> and <code>N</code> , which mean <code>true</code> or <code>false</code>, possible to convert directly in freezed? So I can directly use boolean, instead of String</p>