:type record: aiologger.loggers.json.LogRecord

def formatter_fields_for_record(self, record):
        """
        :type record: aiologger.loggers.json.LogRecord
        """
        datetime_serialized = (
            datetime.now(timezone.utc).astimezone(self.tz).isoformat()
        )

        default_fields = (
            (LOGGED_AT_FIELDNAME, datetime_serialized),
            (LINE_NUMBER_FIELDNAME, record.lineno),
            (FUNCTION_NAME_FIELDNAME, record.funcName),
            (LOG_LEVEL_FIELDNAME, self.level_to_name_mapping[record.levelno]),
            (FILE_PATH_FIELDNAME, record.pathname),
        )

        for field, value in default_fields:
            if field in self.log_fields:
                yield field, value