title: Define a default image if the variable {{image}} is empty
body: <p>My <code>&lt;img&gt;</code>:</p>
  
  <pre><code>&lt;img width="90" height="90"  src="{{image}}" /&gt;
  </code></pre>
  
  <p>Default image folder: <code>assets/img/pic_user.png</code></p>
  
  <p>How can I define a default image that is not defined in the variable: <code>{{image}}</code> ?</p>