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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 create_archive_info(filepath, extracted_path, archive_sha=None):
 """ Saves archive info to a json file :param str filepath: Path to directory of archive :param str extracted_path: Path to directory of archive :param str archive_sha: SHA string created when archive was extracted from zip """


    archive_info = {
        "sha1": archive_sha,
        "filename": os.path.split(filepath)[1],
    }

    with io.open(
        os.path.join(
            extracted_path,
            ".slackviewer_archive_info.json",
        ), 'w+', encoding="utf-8"
    ) as f:
        s = json.dumps(archive_info, ensure_ascii=False)
        s = to_unicode(s)
        f.write(s)