def _get_filename(self):
        if self._fname is None:
            timestamp = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")
            fname = "%s-%s.log" % (timestamp, abs(id(self)))
            self._fname = os.path.join(self.file_path, fname)
        return self._fname
Return a unique file name.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/django/core/mail/backends/filebased.py/EmailBackend._get_filename