title: How can I write a custom Date Format with string into it?
body: <p>silly question here:</p>
  
  <p>I'm willing to write a custom date format in Swift for brazilian pattern, which will be something like:</p>
  
  <pre><code>"20 de Junho, 2017" // 20 of June, 2017
  </code></pre>
  
  <p>I was trying this pattern:</p>
  
  <pre><code>"dd de MMMM, yyyy"
  </code></pre>
  
  <p>But the <code>"de"</code> world is taken as a pattern as well. How can I say that this is a constant?</p>
  
  <p>Thanks</p>