def suffix(self, tupledate):
        """Return the suffix given a (year, month, day) tuple or unixtime"""
        try:
            return '_'.join(map(str, tupledate))
        except:
            # try taking a float unixtime
            return '_'.join(map(str, self.toDate(tupledate)))
Return the suffix given a (year, month, day) tuple or unixtime
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/logfile.py