old_contents: from django.core.urlresolvers import reverse
  from django.http import HttpResponseRedirect
  from django.shortcuts import render
  from .forms import RegistrationForm
  from .models import Registration
  import utils
  
  def handle_registration(request):
      if request.method == 'POST':
          form = RegistrationForm(request.POST)
          if form.is_valid():
              registration = form.save(commit=False)
              # If user is logged-in, let's try sending a tweet!
              if request.user.is_authenticated():
                  registration.user = request.user
                  utils.create_tweet(request.user)
              registration.save()
              return HttpResponseRedirect(reverse('tedx:thanks'))
      else:
          form = RegistrationForm()
      context = {'form': form}
  
      return render(request, 'tedx/index.html', context)
  
  def list_registration(request):
      list_registration = Registration.objects.all()
      context = {'list_registration' : list_registration}
      return render(request, 'tedx/list_registration.html', context)
  
new_contents: from django.contrib.auth.decorators import login_required
  from django.core.exceptions import PermissionDenied
  from django.http import HttpResponseRedirect
  from django.shortcuts import render
  from clubs.models import Team
  from .forms import RegistrationForm
  from .models import Registration
  import utils
  
  def handle_registration(request):
      if request.method == 'POST':
          form = RegistrationForm(request.POST)
          if form.is_valid():
              registration = form.save(commit=False)
              # If user is logged-in, let's try sending a tweet!
              if request.user.is_authenticated():
                  registration.user = request.user
                  utils.create_tweet(request.user)
              registration.save()
              return HttpResponseRedirect(reverse('tedx:thanks'))
      else:
          form = RegistrationForm()
      context = {'form': form}
  
      return render(request, 'tedx/index.html', context)
  
  @login_required
  def list_registration(request):
      tedx_team = Team.objects.get(code_name="tedx_2017_registration")
      is_tedx_member = tedx_team.members.filter(pk=request.user.pk).exists() or\
                       tedx_team.coordinator == request.user
      if not request.user.is_superuser and\
         not is_tedx_member:
          raise PermissionDenied
  
      list_registration = Registration.objects.all()
      context = {'list_registration' : list_registration}
      return render(request, 'tedx/list_registration.html', context)
  
subject: Add permission check for TEDx