def _file_write(self, value, checksum):
        storage = self._storage()
        if storage[:5] == 's3://':
            access_key_id, secret_key, bucket_name, do_space_url = s3_helper.parse_bucket_url(
                storage)
            s3 = s3_helper.get_resource(
                access_key_id, secret_key, do_space_url)
            s3_bucket = self._connect_to_S3_bucket(s3, bucket_name)
            bin_value = base64.b64decode(value)
            fname = hashlib.sha1(bin_value).hexdigest()
            if encryption_enabled:
                s3.Object(s3_bucket.name, fname).put(Body=bin_value, ServerSideEncryption='AES256')
            else:
                s3.Object(s3_bucket.name, fname).put(Body=bin_value)

        else: # falling back on Odoo's local filestore
            fname = super(S3Attachment, self)._file_write(value, checksum)

        return fname