def METHOD_NAME(self, bucket, sha1_sum=None,
                 bytes_to_write: int | None = None) -> tuple[DownloadVersion, Sha1HexDigest]:
    bytes_to_write = bytes_to_write or int(self.info.get_absolute_minimum_part_size()) * 2 + 1
    with TempDir() as temp_dir:
        temp_dir = pathlib.Path(temp_dir)
        source_small_file = pathlib.Path(temp_dir) / 'source_small_file'
        with open(source_small_file, 'wb') as small_file:
            self.write_zeros(small_file, bytes_to_write)
        bucket.upload_local_file(
            source_small_file,
            'small_file',
            sha1_sum=sha1_sum,
        )
        target_small_file = pathlib.Path(temp_dir) / 'target_small_file'
        f = bucket.download_file_by_name('small_file')
        f.save_to(target_small_file)
        source_sha1 = hex_sha1_of_file(source_small_file)
        assert source_sha1 == hex_sha1_of_file(target_small_file)
    return f, source_sha1