old_contents: from django.core.urlresolvers import reverse_lazy
  from django.views.generic import CreateView
  from django.views.generic import DetailView
  from django.views.generic import ListView
  
  from pure_pagination import PaginationMixin
  
  from warp.users.models import User
  from .forms import PresentationCreateForm
  from .models import Presentation
  
  
  class PresentationList(PaginationMixin, ListView):
      model = Presentation
      paginate_by = 9
      context_object_name = 'presentations'
      ordering = ['-pk']
  
  
  class PresentationDetail(DetailView):
      model = Presentation
      context_object_name = 'presentation'
  
  
  class PresentationCreate(LoginRequiredMixin, CreateView):
      model = Presentation
      form_class = PresentationCreateForm
      success_url = reverse_lazy('presentation:list')
      template_name_suffix = '_create'
  
      def form_valid(self, form):
          form.user = self.request.user
          form.cleaned_data['author'] = User.objects.get(username=form.user.username)
          return super(PresentationCreate, self).form_valid(form)
  
  
  
new_contents: from django.core.urlresolvers import reverse_lazy
  from django.views.generic import CreateView
  from django.views.generic import DetailView
  from django.views.generic import ListView
  
  from django.contrib.auth.mixins import LoginRequiredMixin
  from pure_pagination import PaginationMixin
  
  from warp.users.models import User
  from .forms import PresentationCreateForm
  from .models import Presentation
  
  
  class PresentationList(PaginationMixin, ListView):
      model = Presentation
      paginate_by = 9
      context_object_name = 'presentations'
      ordering = ['-pk']
  
  
  class PresentationDetail(DetailView):
      model = Presentation
      context_object_name = 'presentation'
  
  
  class PresentationCreate(LoginRequiredMixin, CreateView):
      model = Presentation
      form_class = PresentationCreateForm
      success_url = reverse_lazy('presentation:list')
      template_name_suffix = '_create'
  
      def form_valid(self, form):
          form.user = self.request.user
          form.cleaned_data['author'] = User.objects.get(username=form.user.username)
          return super(PresentationCreate, self).form_valid(form)
  
  
  
subject: Update views.py