old_contents: from cms import sitemaps
  from cms.apps.pages.models import ContentBase
  from cms.models import HtmlField, PageBase
  from django.db import models
  from historylinks import shortcuts as historylinks
  
  
  class Careers(ContentBase):
  
      classifier = 'apps'
      urlconf = '{{ project_name }}.apps.careers.urls'
  
      per_page = models.PositiveIntegerField(
          'careers per page',
          default=10,
          blank=True,
          null=True
      )
  
      def __str__(self):
          return self.page.title
  
  
  class Career(PageBase):
  
      page = models.ForeignKey(
          Careers
      )
  
      title = models.CharField(
          max_length=256,
      )
  
      slug = models.CharField(
          max_length=256,
          unique=True
      )
  
      location = models.CharField(
          max_length=256,
          blank=True,
          null=True
      )
  
      summary = models.TextField(
          blank=True,
          null=True
      )
  
      description = HtmlField()
  
      email_address = models.EmailField()
  
      order = models.PositiveIntegerField(
          default=0
      )
  
      class Meta:
          ordering = ['order']
  
      def __str__(self):
          return self.title
  
      def get_absolute_url(self):
          return self.page.page.reverse('career_detail', kwargs={
              'slug': self.slug,
          })
  
  historylinks.register(Career)
  sitemaps.register(Career)
  
new_contents: from cms import sitemaps
  from cms.apps.pages.models import ContentBase
  from cms.models import HtmlField, PageBase
  from django.db import models
  from historylinks import shortcuts as historylinks
  
  
  class Careers(ContentBase):
  
      classifier = 'apps'
      urlconf = '{{ project_name }}.apps.careers.urls'
  
      per_page = models.PositiveIntegerField(
          'careers per page',
          default=10,
          blank=True,
          null=True
      )
  
      def __str__(self):
          return self.page.title
  
  
  class Career(PageBase):
  
      page = models.ForeignKey(
          Careers
      )
  
      location = models.CharField(
          max_length=256,
          blank=True,
          null=True
      )
  
      summary = models.TextField(
          blank=True,
          null=True
      )
  
      description = HtmlField()
  
      email_address = models.EmailField()
  
      order = models.PositiveIntegerField(
          default=0
      )
  
      class Meta:
          ordering = ['order']
  
      def __str__(self):
          return self.title
  
      def get_absolute_url(self):
          return self.page.page.reverse('career_detail', kwargs={
              'slug': self.slug,
          })
  
  historylinks.register(Career)
  sitemaps.register(Career)
  
subject: Remove duplicate fields from Career