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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 _parse_alt_url(html_chunk):
 """ Parse URL from alternative location if not found where it should be. Args: html_chunk (obj):
 HTMLElement containing slice of the page with details. Returns: str: Book's URL. """

    url_list = html_chunk.find("a", fn=has_param("href"))
    url_list = map(lambda x: x.params["href"], url_list)
    url_list = filter(lambda x: not x.startswith("autori/"), url_list)

    if not url_list:
        return None

    return normalize_url(BASE_URL, url_list[0])