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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _download_file(self, dss_file, dest_path, num_retries=10, min_delay_seconds=0.25):
 """ Attempt to download the data. If a retryable exception occurs, we wait a bit and retry again. The delay increases each time we fail and decreases each time we successfully read a block. We set a quota for the number of failures that goes up with every successful block read and down with each failure. If we can, we will attempt HTTP resume. However, we verify that the server supports HTTP resume. If the ranged get doesn't yield the correct header, then we start over. """

        directory, _ = os.path.split(dest_path)
        if directory:
            try:
                os.makedirs(directory)
            except OSError as e:
                if e.errno != errno.EEXIST:
                    raise
        with atomic_write(dest_path, mode="wb", overwrite=True) as fh:
            if dss_file.size == 0:
                return

            download_hash = self._do_download_file(dss_file, fh, num_retries, min_delay_seconds)

            if download_hash.lower() != dss_file.sha256.lower():
                # No need to delete what's been written. atomic_write ensures we're cleaned up
                logger.error("%s", "File {}: GET FAILED. Checksum mismatch.".format(dss_file.uuid))
                raise ValueError("Expected sha256 {} Received sha256 {}".format(
                    dss_file.sha256.lower(), download_hash.lower()))