title: Replace src of an image with jquery
body: <p>I have a website and based on language <code>en, sq or el,</code> I want to change image source. So I have a folder named screenshots then there are three folders: <code>en , sq and el</code>.</p>
  
  <p>For example the URL for a picture named 'slide-phone.png' is:</p>
  
  <pre><code>img/screenshots/en/slide-phone.png
  img/screenshots/sq/slide-phone.png
  img/screenshots/el/slide-phone.png
  </code></pre>
  
  <p>On the html text I have a prameter : <code>{{ _('en') }}</code> that can have one of those value: <code>en , sq and el</code>. In this case is en.</p>
  
  <pre><code>&lt;html lang="{{ _('en') }}"&gt;
  &lt;head&gt;
  &lt;script type="text/javascript"&gt;
    img_url = 'img/screenshots/'+"{{ _('en') }}"+'/slide-phone.png';
    console.log("img is:" , img_url);
    $('#slide-phone-img').attr('src',img_url);
  &lt;/script&gt;
  </code></pre>
  
  <p>The HTML div is like this:</p>
  
  <pre><code> &lt;img  id="slide-phone-img" src="" &gt;
  </code></pre>
  
  <p>The console gives the right link: <code>img is: img/screenshots/en/slide-phone.png</code> but the src attribute is empty!</p>
  
  <p>Why is happening this, I don't get it, can someone help me?</p>