title: Strings won't be translated in Django using format function available in Python 2.7
body: <p>Does the new and recommended way to format strings available in Python 2.7 using <code>format</code> result in a non translated string in Django?</p>
  
  <p>The strings are in the <code>.po</code> file, translated, but it won't be translated on the website. For example:</p>
  
  <pre><code>from django.utils.translation import ugettext as _
  
  website_name = "Stackoverflow"
  title = _(u"{sitename} is a good website".format(sitename=website_name))
  </code></pre>
  
  <p>The <code>.po</code> file after translating the string looks like this:</p>
  
  <pre><code>#: path/to/file.py:4
  msgid "{sitename} is a good website"
  msgstr "{sitename} ist eine gute Website"
  </code></pre>
  
  <p>After running <code>django-admin.py compilemessages</code> and restarting the webserver, on the processed HTML page it is still in english, while all the other strings are being translated. Furthermore, while all strings using <code>format</code> are not translated, strings formatted using the <code>%</code> operator are translated as expected. It is also not a gettext/ugettext issue, as the problem is the same with both functions.</p>