title: Make all items in a QTreeWidget editable
body: <p>Is it possible to make all items in a QTreeWidget editable on user double-click? </p>
  
  <p><a href="https://i.stack.imgur.com/7ryBi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7ryBi.png" alt="enter image description here"></a></p>
  
  <p>I have already set the only editing-related property I found - <code>editTriggers</code> - to <code>DoubleClicked|EditKeyPressed</code>, but the items are still not editable.</p>