def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def do_register_cli_opts(opt, ignore_errors=False):
    # TODO: This function has broken name, it should work with lists :/
    if not isinstance(opt, (list, tuple)):
        opts = [opt]
    else:
        opts = opt

    try:
        cfg.CONF.register_cli_opts(opts)
    except:
        if not ignore_errors:
            raise