def __init__(self, name, host='127.0.0.1', port=27017):
        self.name = name
        self.host = host
        self.port = port
def _verify_toplevel_json(self, replay_data):
        fn = self._filename

        if "version" not in replay_data:
            raise TransactionReplayError(fn, _('Missing key "{key}".'.format(key="version")))

        self._assert_type(replay_data["version"], str, "version", "string")

        _check_version(replay_data["version"], fn)