def import_data(self, data):
        """Import additional data for tuning

        Parameters
        ----------
        data:
            a list of dictionarys, each of which has at least two keys, 'parameter' and 'value'
        """
        _completed_num = 0
        for trial_info in data:
            logger.info("Importing data, current processing progress %s / %s" %(_completed_num, len(data)))
            _completed_num += 1
            assert "parameter" in trial_info
            _params = trial_info["parameter"]
            assert "value" in trial_info
            _value = trial_info['value']
            if not _value:
                logger.info("Useless trial data, value is %s, skip this trial data." %_value)
                continue
            _params_tuple = convert_dict2tuple(_params)
            self.supplement_data[_params_tuple] = True
        logger.info("Successfully import data to grid search tuner.")