This error usually means you've forgotten a closing quote somewhere in the template you're trying to render. For example: {% url 'my_view %}
(wrong) instead of {% url 'my_view' %}
(correct). In this case it's the colon that's causing the problem. Normally you'd edit the template to use the correct {% url %}
syntax.
But there's no reason why the django admin site would throw this, since it would know it's own syntax. My best guess is therefore that grapelli
is causing your problem since it changes the admin templates. Does removing grappelli from installed apps help?