title: Django: TypeError: context must be a dict rather than str
body: <p>I wanto to redirect to an url if the object of GroupMember doesn't exist but shows this error:</p>
  
  <p>TypeError: context must be a dict rather than str.</p>
  
  <p>Here is my view:</p>
  
  <pre><code>class GroupDetail(DetailView):
  
  template_name = "group_detail.html"
  model = Group
  
  def get_context_data(self, **kwargs):
      context = super(GroupDetail, self).get_context_data(**kwargs)
      # Code
      try:
          group_member = GroupMember.objects.get(member=volunteer, group=group)
          context['group_member'] = group_member
          # Code
          return context
      except:
          return reverse('users:home')
  </code></pre>
  
  <p>I try with redirect and reverse_lazy but shows the same error and I tried with</p>
  
  <pre><code>reverse('users:home', {}), reverse('users:home', kwargs={}) 
  </code></pre>
  
  <p>and</p>
  
  <pre><code>reverse('users:home', kwargs=None)
  </code></pre>