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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_nameservers(domain):
 """ Looks for domain nameservers and returns the IPs of the nameservers as a list. The list is empty, if no nameservers were found. Needed associated domain zone name for lookup. """

        nameservers = []
        rdtypes_ns = ['SOA', 'NS']
        rdtypes_ip = ['A', 'AAAA']
        for rdtype_ns in rdtypes_ns:
            for rdata_ns in Provider._dns_lookup(domain, rdtype_ns):
                for rdtype_ip in rdtypes_ip:
                    for rdata_ip in Provider._dns_lookup(rdata_ns.to_text().split(' ')[0],
                                                         rdtype_ip):
                        if rdata_ip.to_text() not in nameservers:
                            nameservers.append(rdata_ip.to_text())
        LOGGER.debug('DNS Lookup => %s IN NS %s', domain, ' '.join(nameservers))
        return nameservers