def _create_digest_key(self, start_date, key_prefix):
        """Computes an Amazon S3 key based on the provided data.

        The computed is what would have been placed in the S3 bucket if
        a log digest were created at a specific time. This computed key
        does not have to actually exist as it will only be used to as
        a Marker parameter in a list_objects call.

        :return: Returns a computed key as a string.
        """
        # Subtract one minute to ensure the dates are inclusive.
        date = start_date - timedelta(minutes=1)
        template = ('AWSLogs/{account}/CloudTrail-Digest/{source_region}/'
                    '{ymd}/{account}_CloudTrail-Digest_{source_region}_{name}_'
                    '{home_region}_{date}.json.gz')
        key = template.format(account=self.account_id, date=format_date(date),
                              ymd=date.strftime('%Y/%m/%d'),
                              source_region=self.trail_source_region,
                              home_region=self.trail_home_region,
                              name=self.trail_name)
        if key_prefix:
            key = key_prefix + '/' + key
        return key
dataset/ETHPy150Open aws/aws-cli/awscli/customizations/cloudtrail/validation.py/DigestProvider._create_digest_key/original