'Returns total points by user.'

@classmethod
def get_total(cls, user):

    key = cls.get_key(('get_total:%s' % user.id))
    val = cache.get(key)
    if (val is not None):
        return val
    val = ReviewerScore.objects.filter(user=user).aggregate(total=Sum('score')).values()[0]
    if (val is None):
        val = 0
    cache.set(key, val, None)
    return val
