':param target_url: The url object we can use to extract some information
:return: From the domain, get a list of FQDN, rootDomain and IP address.'

def _get_to_check(self, target_url):

    def addrinfo(url):
        return [x[4][0] for x in socket.getaddrinfo(url.get_domain(), 0)]
    def getfqdn(url):
        return [socket.getfqdn(url.get_domain())]
    def root_domain(url):
        if (not is_ip_address(url.get_domain())):
            return [url.get_root_domain()]
        return []
    res = set()
    for func in (addrinfo, getfqdn, root_domain):
        try:
            data_lst = func(target_url)
        except Exception:
            pass
        else:
            for data in data_lst:
                res.add(data)
    return res
