def METHOD_NAME(self, db_session, factories):
    factories.DeveloperToken(
        expires=datetime(2014, 5, 6, 7, 8, 9),
        refresh_token_expires=datetime(2014, 5, 13, 7, 8, 9),
    )
    factories.DeveloperToken(
        expires=(datetime.utcnow() - timedelta(hours=2)),
        refresh_token_expires=(datetime.utcnow() - timedelta(seconds=1)),
    )
    assert db_session.query(Token).count() == 2
    purge_expired_tokens()
    assert not db_session.query(Token).count()