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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 prune_urls(url_set, start_url, allowed_list, ignored_list):
 """Prunes URLs that should be ignored."""

    result = set()

    for url in url_set:
        allowed = False
        for allow_url in allowed_list:
            if url.startswith(allow_url):
                allowed = True
                break

        if not allowed:
            continue

        ignored = False
        for ignore_url in ignored_list:
            if url.startswith(ignore_url):
                ignored = True
                break

        if ignored:
            continue

        prefix, suffix = (url.rsplit('.', 1) + [''])[:2]
        if suffix.lower() in IGNORE_SUFFIXES:
            continue

        result.add(url)

    return result