old_contents: # -*- coding: utf-8 -*-
  from django.db import models
  from django.utils.translation import ugettext_lazy as _
  
  from opps.core.models import Publishable
  
  
  class Source(Publishable):
  
      name = models.CharField(_(u"Name"), max_length=255)
      slug = models.SlugField(_(u"Slug"), max_length=140, unique=True,
                              db_index=True)
      url = models.URLField(_(u'URL'), max_length=200, blank=True, null=True)
      feed = models.URLField(_(u'Feed URL'), max_length=200, blank=True,
                             null=True)
  
      def __unicode__(self):
          return self.slug
  
new_contents: # -*- coding: utf-8 -*-
  from django.db import models
  from django.utils.translation import ugettext_lazy as _
  
  from opps.core.models import Publishable
  
  
  class Source(Publishable):
  
      name = models.CharField(_(u"Name"), max_length=255)
      slug = models.SlugField(_(u"Slug"), max_length=140, unique=True,
                              db_index=True)
      url = models.URLField(_(u'URL'), max_length=200, blank=True, null=True)
      feed = models.URLField(_(u'Feed URL'), max_length=200, blank=True,
                             null=True)
  
      class META:
          verbose_name = _('Source')
          verbose_name_plural = _('Sources')
  
      def __unicode__(self):
          return self.slug
  
subject: Add verbose name (plural) Sources models