title: Use admin login form then redirect back to page
body: <p>Right now I have an app here:</p>
  
  <pre><code>htttp://localhost/main
  </code></pre>
  
  <p>Which requires a login for django's authentication. I want to use the admin login form <code>http://localhost/admin/login</code>. The problem is that by default the admin login redirects back to itself, but I want it to redirect back to <code>http://localhost/main</code>. Is there a way I can get this done?</p>
  
  <p>This is my view currently</p>
  
  <pre><code>@login_required(login_url='/admin', redirect_field_name='main'
  def main_view(request):
       return render(request, 'main_site.html')
  </code></pre>
  
  <p>By doing this, it just redirects me to the following URL:</p>
  
  <pre><code>http://localhost/admin/login/?next=/admin/%3Fmain%3D/main/
  </code></pre>
  
  <p>But I need it to be</p>
  
  <pre><code>http://localhost/admin/login/?next=/main/
  </code></pre>