old_contents: from django.db import models
  from django_amber.models import ModelWithContent, ModelWithoutContent
  
  
  class Page(ModelWithContent):
      title = models.CharField(max_length=255)
      callout_big_1 = models.CharField(max_length=255)
      callout_big_2 = models.CharField(max_length=255)
      callout_small = models.CharField(max_length=255)
      tito_required = models.BooleanField(default=False)
  
      dump_dir_path = 'pages'
  
  
  class NewsItem(ModelWithContent):
      title = models.CharField(max_length=255)
      date = models.DateField()
  
      dump_dir_path = 'news'
  
  
  class Speaker(ModelWithContent):
      name = models.CharField(max_length=255)
  
      dump_dir_path = 'speakers'
  
  
  class Session(ModelWithContent):
      speaker = models.ForeignKey(Speaker, null=True)
      title = models.CharField(max_length=255)
      subtitle = models.CharField(max_length=255, null=True)
  
      dump_dir_path = 'sessions'
  
      def session_type(self):
          return self.key.split('/', 1)[0]
  
      def slug(self):
          return self.key.split('/', 1)[1]
  
  
  class Sponsor(ModelWithContent):
      TIERS = (
          ('gold', 'gold'),
          ('silver', 'silver'),
          ('bronze', 'bronze'),
      )
      name = models.CharField(max_length=255)
      tier = models.CharField(max_length=255, choices=TIERS)
      website = models.CharField(max_length=255)
      twitter_handle = models.CharField(max_length=255)
      logo_filename = models.CharField(max_length=255)
  
      dump_dir_path = 'sponsors'
  
  
  class Redirection(ModelWithoutContent):
      new_url = models.CharField(max_length=255)
  
      dump_dir_path = 'redirections'
  
  
  class ScheduleSlot(ModelWithoutContent):
      session = models.ForeignKey(Session, null=True)
      title = models.CharField(max_length=255)
      date = models.CharField(max_length=40)
      room = models.CharField(max_length=40)
      time = models.CharField(max_length=40)
  
      dump_dir_path = 'schedule'
  
new_contents: from django.db import models
  from django_amber.models import ModelWithContent, ModelWithoutContent
  
  
  class Page(ModelWithContent):
      title = models.CharField(max_length=255)
      callout_big_1 = models.CharField(max_length=255)
      callout_big_2 = models.CharField(max_length=255)
      callout_small = models.CharField(max_length=255)
      tito_required = models.BooleanField(default=False)
  
      dump_dir_path = 'pages'
  
  
  class NewsItem(ModelWithContent):
      title = models.CharField(max_length=255)
      date = models.DateField()
  
      dump_dir_path = 'news'
  
  
  class Speaker(ModelWithContent):
      name = models.CharField(max_length=255)
  
      dump_dir_path = 'speakers'
  
  
  class Session(ModelWithContent):
      speaker = models.ForeignKey(Speaker, null=True)
      title = models.CharField(max_length=255)
      subtitle = models.CharField(max_length=255, null=True)
  
      dump_dir_path = 'sessions'
  
      def session_type(self):
          return self.key.split('/', 1)[0]
  
      def slug(self):
          return self.key.split('/', 1)[1]
  
      def time(self):
          return self.scheduleslot.time
  
      def date(self):
          return self.scheduleslot.date
  
      def room(self):
          return self.scheduleslot.room
  
  
  class Sponsor(ModelWithContent):
      TIERS = (
          ('gold', 'gold'),
          ('silver', 'silver'),
          ('bronze', 'bronze'),
      )
      name = models.CharField(max_length=255)
      tier = models.CharField(max_length=255, choices=TIERS)
      website = models.CharField(max_length=255)
      twitter_handle = models.CharField(max_length=255)
      logo_filename = models.CharField(max_length=255)
  
      dump_dir_path = 'sponsors'
  
  
  class Redirection(ModelWithoutContent):
      new_url = models.CharField(max_length=255)
  
      dump_dir_path = 'redirections'
  
  
  class ScheduleSlot(ModelWithoutContent):
      session = models.ForeignKey(Session, null=True)
      title = models.CharField(max_length=255)
      date = models.CharField(max_length=40)
      room = models.CharField(max_length=40)
      time = models.CharField(max_length=40)
  
      dump_dir_path = 'schedule'
  
subject: Add helper methods to session model