allauth

Getting the following error when I try to run python manage.py syncdb:
CommandError: One or more models did not validate:
socialaccount.socialapp: 'sites' has an m2m relation with model <class 'django.contrib.sites.models.Site'>, which has either not been installed or is abstract.


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/usr/lib/python2.7/django/contrib/sites/models.py: class Site
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@python_2_unicode_compatible
class Site(models.Model):

    domain = models.CharField(_('domain name'), max_length=100,
        validators=[_simple_domain_name_validator])
    name = models.CharField(_('display name'), max_length=50)
    objects = SiteManager()

    class Meta:
        db_table = 'django_site'
        verbose_name = _('site')
        verbose_name_plural = _('sites')
        ordering = ('domain',)

    def __str__(self):
        return self.domain


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foo/allauth/socialaccount/models.py class SocialApp
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@python_2_unicode_compatible
class SocialApp(models.Model):
    objects = SocialAppManager()

    provider = models.CharField(max_length=30,
                                choices=providers.registry.as_choices())
    name = models.CharField(max_length=40)
    client_id = models.CharField(max_length=100,
                                 help_text='App ID, or consumer key')
    key = models.CharField(max_length=100,
                           blank=True,
                           help_text='Key (Stack Exchange only)')
    secret = models.CharField(max_length=100,
                              help_text='API secret, client secret, or'
                              ' consumer secret')
    # Most apps can be used across multiple domains, therefore we use
    # a ManyToManyField. Note that Facebook requires an app per domain
    # (unless the domains share a common base name).
    # blank=True allows for disabling apps without removing them
    sites = models.ManyToManyField(Site, blank=True)

    def __str__(self):
        return self.name


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