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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_files_if_not_in_manifest(files_iterator, output_path):
 """Download the given files to the given path, unless in manifest."""

    local_manifest = read_local_manifest(output_path)
    with open(get_local_manifest_path(output_path), 'a') as manifest_fh:
        for (file_name, width) in files_iterator:
            if is_file_in_manifest(file_name, width, local_manifest):
                logging.info('Skipping file %s', file_name)
                continue
            try:
                download_file(file_name, output_path, width=width)
                write_file_to_manifest(file_name, width, manifest_fh)
            except DownloadException, e:
                logging.error("Could not download %s: %s", file_name, e.message)