title: DRF Custom permission
body: <p>Im trying to build a custom permission in Django rest framework - </p>
  
  <pre><code>class GroupBasePermission(permissions.BasePermission):
  
      group_name = ""
  
      def has_permission(self, request, view):
          """
          Should simply return, or raise a 403 response.
          """
          print 'self.group_name == ', self.group_name
          try:
              request.user.groups.get(name=self.group_name)    
          except Group.DoesNotExist:
              print 'group does not exist'
              msg = ('Permission denied.')
              data = {'detail': six.text_type(msg)}
              #return Response(data, status=status.HTTP_403_FORBIDDEN)
              return HttpResponseForbidden()
  
  class HRAdminGroupPermission(GroupBasePermission):
      """
          Checks to see if a user is in a particular group
      """
  
      group_name = "HR Admin1"
  </code></pre>
  
  <p>and here is my view</p>
  
  <pre><code>class CompanyCreateApiView(LoginRequiredMixin,OTPRequiredMixin,GroupRequiredMixin,CreateAPIView):
  
      permission_classes = (IsAuthenticated, HRAdminGroupPermission,)
      authentication_classes = (SessionAuthentication,)
      group_required = 'HR Admin1'
  
  
      def post(self, request, *args, **kwargs):
          for each in self.request.user.groups.all():
              print 'self.request.user.group == ', each.name
  </code></pre>
  
  <p>When I call this API using a user(GROUP-- HR ADMIN) it does not throws me 403 forbidden error even though I see the print msg in the permission exception.</p>
  
  <p>How can I fix this issue?</p>