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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 linkify(self, hosts=None, realms=None, forced_realms_hostgroups=True):
 """Link hostgroups with hosts and realms :param hosts: all Hosts :type hosts: alignak.objects.host.Hosts :param realms: all Realms :type realms: alignak.objects.realm.Realms :return: None """

        self.linkify_hostgroups_hosts(hosts)
        self.linkify_hostgroups_realms_hosts(realms, hosts, forced_realms_hostgroups)