old_contents: from decimal import Decimal
  
  from django.conf import settings
  from django.contrib.auth.decorators import login_required
  from django.shortcuts import get_object_or_404, render, reverse
  from django.utils.translation import ugettext_lazy as _
  from django.views.decorators.csrf import csrf_exempt
  
  from paypal.standard.forms import PayPalPaymentsForm
  
  from ..orders.models import Order
  
  
  @login_required
  def payment_process(request):
      order_id = request.session.get('order_id')
      order = get_object_or_404(Order, id=order_id)
      host = request.get_host()
  
      paypal_dict = {
          'business': settings.ADMIN_MAIL,
          'amount': '{}'.format(
              order.get_total_cost().quantize(Decimal('.01'))),
          'item_name': _('Order {}').format(order.id),
          'invoice': str(order.id),
          'currency_code': 'USD',
          'notify_url': 'http://{}{}'.format(host, reverse('paypal_ipn')),
          'return_url': 'http://{}{}'.format(host, reverse('payment:done')),
          'cancel_return': 'http://{}{}'.format(
              host, reverse('payment:canceled')),
      }
  
      context = {
          'order': order,
          'form': PayPalPaymentsForm(initial=paypal_dict)
      }
      return render(request, 'payment/process.html', context)
  
  
  @csrf_exempt
  @login_required
  def payment_done(request):
      return render(request, 'payment/done.html')
  
  
  @csrf_exempt
  @login_required
  def payment_canceled(request):
      return render(request, 'payment/canceled.html')
  
new_contents: from decimal import Decimal
  
  from django.conf import settings
  from django.contrib.auth.decorators import login_required
  from django.shortcuts import get_object_or_404, render, reverse
  from django.utils.translation import ugettext_lazy as _
  from django.views.decorators.csrf import csrf_exempt
  
  from paypal.standard.forms import PayPalPaymentsForm
  
  from ..orders.models import Order
  
  
  @login_required
  def payment_process(request):
      order_id = request.session.get('order_id')
      order = get_object_or_404(Order, id=order_id)
      host = request.get_host()
  
      paypal_dict = {
          'business': settings.ADMIN_MAIL,
          'amount': '{}'.format(
              order.get_total_cost().quantize(Decimal('.01'))),
          'item_name': _('Order {}').format(order.id),
          'invoice': str(order.id),
          'currency_code': 'USD',
          'notify_url': 'http://{}{}'.format(host, reverse('paypal-ipn')),
          'return_url': 'http://{}{}'.format(host, reverse('payment:done')),
          'cancel_return': 'http://{}{}'.format(
              host, reverse('payment:canceled')),
      }
  
      context = {
          'order': order,
          'form': PayPalPaymentsForm(initial=paypal_dict)
      }
      return render(request, 'payment/process.html', context)
  
  
  @csrf_exempt
  @login_required
  def payment_done(request):
      return render(request, 'payment/done.html')
  
  
  @csrf_exempt
  @login_required
  def payment_canceled(request):
      return render(request, 'payment/canceled.html')
  
subject: Fix 'notify_url'