models.py

from django.db import models
from django.contrib.auth.models import User

class Category(models.Model):
    name = models.CharField(max_length = 128, unique = True)
    views = models.IntegerField(default = 0)
    likes = models.IntegerField(default = 0)

    def __unicode__(self):
        return self.name

class Page(models.Model):
    category = models.ForeignKey(Category)
    title = models.CharField(max_length = 128)
    url = models.URLField(unique = True)
    views = models.IntegerField(default = 0)

    def __unicode__(self):
        return self.title

class UserProfile(models.Model):
    # This line is required. Links UserProfile to a User model instance.
    user = models.OneToOneField(User)

    # The additional attribute we wish to include.
    website = models.URLField(blank = True)
    picture = models.ImageField(upload_to = 'profile_images', blank = True)

    # Override the __unicode__() method to return out something meaningful!
    def __unicode__(self):
        return self.user.username