old_contents: from django.contrib.auth.models import AbstractUser, Group
  from django.db import models
  
  
  class ForumUser(AbstractUser):
      def __unicode__(self):
          return '%(username)s (%(email)s)' % {
              'username': self.username,
              'email': self.email
          }
  
new_contents: from django.contrib.auth.models import AbstractUser, Group
  from django.db import models
  
  
  class ForumUser(AbstractUser):
      items_per_page = models.PositiveSmallIntegerField(blank=True, null=True)
  
      def __unicode__(self):
          return '%(username)s (%(email)s)' % {
              'username': self.username,
              'email': self.email
          }
  
subject: Add items per page as a preference to the forumm user model