def get(self, id, pk='id', deleted=False):
        try:
            if pk == 'id':
                id = int(id)
            if deleted:
                spec = {pk: id}
            else:
                spec = {pk: id, 'data': {'$exists': 1}}
            fields = {'_id': 0}
            row = self.db.docs.find_one(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return Document(**row)
        raise NotFoundError('%s %s not found' % (pk, id))
def permutation_subjects_ktst(y):
    """Permute class labels of Contextual Disorder dataset for KTST.
    """
    yp = np.random.randint(0, 2, len(y)/2)
    yp = np.concatenate((yp, np.logical_not(yp).astype(int)))
    y_perm = np.arange(len(y))
    for i in range(len(y)/2):
        if yp[i] == 1:
            y_perm[i] = len(y)/2+i
            y_perm[len(y)/2+i] = i
    return y_perm