@csv.DictReader.fieldnames.getter
    def fieldnames(self):
        if self._fieldnames is None:
            try:
                self._fieldnames = self.reader.next()
            except __HOLE__:
                pass
            self.line_num = self.reader.line_num
            self.__mv_fieldnames = []
            self.__fieldnames = []
            for name in self._fieldnames:
                if name.startswith('__mv_'):
                    # Store this pair: <fieldname>, __mv_<fieldname>
                    self.__mv_fieldnames.append((name[len('__mv_'):], name))
                else:
                    self.__fieldnames.append(name)
        return self.__fieldnames
dataset/ETHPy150Open hvandenb/splunk-elasticsearch/search-elasticsearch/bin/splunklib/searchcommands/splunk_csv/dict_reader.py/DictReader.fieldnames