title: Set "SF UI Display Bold" as label font
body: <p>I have a problem with setting the font of my label to SF UI Display Bold.</p>
  
  <p>I don't wanna set this durable, only if a boolean is false.</p>
  
  <pre><code>if (value.messageReaded == false) {
      cell.subjectLabel?.font = UIFont(name:"SF UI Display Bold", size: 17.0)
  }
  </code></pre>
  
  <p>Unfortunately, my approach isn't working with this font.</p>
  
  <p>Does somebody of you know the correct title of the "SF UI Display Bold" font in swift? </p>
  
  <p>Thanks!</p>