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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 get_whois_tags(ip_address):
 """ Get list of tags with `address` for given `ip_address`. Args: index_page (str):
 HTML content of the page you wisht to analyze. Returns: list: List of :class:`.SourceString` objects. """

    whois = IPWhois(ip_address).lookup_whois()
    nets = whois.get("nets", None)

    if not nets:
        return []

    # parse cities
    cities = [
        net["city"]
        for net in nets
        if net.get("city", None)
    ]

    # parse address tags
    address_list = []
    for net in nets:
        address = net.get("address", None)
        if not address:
            continue

        # filter company name
        if "description" in net and net["description"]:
            address = address.replace(net["description"], "").strip()

        if "\n" in address:
            address = ", ".join(address.splitlines())

        address_list.append(address)

    return [
        SourceString(val, source="Whois")
        for val in set(cities + address_list)
    ]