title: Django: The included urlconf core.urls doesn't have any patterns in it
body: <p>I'm having some weird issues with class-based-views and reverse_lazy.</p>
  
  <p>Following error shows up when calling the website:</p>
  
  <pre><code>ImproperlyConfigured at /dashboard/student/
  The included urlconf core.urls doesn't have any patterns in it
  </code></pre>
  
  <p>My views.py:</p>
  
  <pre><code>class DashStudentMain(TemplateView):
      model_class = None
      template_name = 'learn/dashboard/snip_student_1.html'
      tab_list = {
          ("Main", reverse_lazy('dash_student_main_url')),
          #("History", reverse_lazy('dash_student_main_url'))
      }
      active_tab = "Main"
  </code></pre>
  
  <p>My core.urls:</p>
  
  <pre><code>from django.conf.urls.defaults import patterns, include, url
  from django.contrib import admin
  from django.views.generic import RedirectView
  from django.conf import settings
  
  admin.autodiscover()
  
  urlpatterns = patterns(
      '',
      url(r'^$', 'core.views.home', name='home_url'),
      url(r'^home', 'core.views.home'),
      url(r'^dashboard/', include('tc_learn.dashboard.urls')),
      ...
  )
  </code></pre>
  
  <p>My tc_learn.dashboard.urls:</p>
  
  <pre><code>from django.conf.urls.defaults import patterns, url
  from .views import DashStudentMain, DashStudentHistory
  
  urlpatterns = patterns(
      # Student + Tabs
      url(r"^", DashStudentMain.as_view()),
      url(r"^student/$", DashStudentMain.as_view(), name="dash_student_main_url"),
      url(r"^student/history/$", DashStudentHistory.as_view(), name="dash_student_history_url"),
  </code></pre>
  
  <p>I've </p>
  
  <ul>
  <li>restarted the server, to make sure urls were loaded properly</li>
  <li>commented out <strong>("Main", reverse_lazy('dash_student_main_url'))</strong> to make sure that the urls.py syntax is fine</li>
  <li>deleted the line <strong>url(r"^", DashStudentMain.as_view()),</strong> since it's not used anyway, but without it /dashboard/student doesn't work at all..</li>
  </ul>
  
  <p>Any idea what I might be missing? Thanks!</p>
  
  <p>EDIT:
  It looks like the issue is coming from the tab_list object.
  When I directly assign the object via <code>tab_list = reverse_lazy('dash_student_main_url')</code>, the code works fine. When I use it inside a list, it's showing that error. Does anyone know of work-around for this scenario?</p>