title: ugettext and ugettext_lazy
body: <p>Could you explain what principal difference between <code>ugettext</code> and <code>ugettext_lazy</code>?</p>
  <p>When I'm trying to</p>
  <pre class="lang-py prettyprint-override"><code>return HttpResponse(ugettext_lazy(&quot;Hello&quot;))
  </code></pre>
  <p>I see nothing, but</p>
  <pre class="lang-py prettyprint-override"><code>return HttpResponse(ugettext(&quot;Hello&quot;))
  </code></pre>
  <p>is working.</p>
  <p>Why?</p>