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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 _config_net_topology(self, conf):
 """ Initialize and populate all the network related elements, like reserving ips and populating network specs of the given confiiguration spec Args: conf (dict):
 Configuration spec to initalize Returns: None """

        conf = self._init_net_specs(conf)
        mgmts = self._select_mgmt_networks(conf)
        self._validate_netconfig(conf)
        allocated_subnets, conf = self._allocate_subnets(conf)
        try:
            self._add_mgmt_to_domains(conf, mgmts)
            self._register_preallocated_ips(conf)
            self._allocate_ips_to_nics(conf)
            self._set_mtu_to_nics(conf)
            self._add_dns_records(conf, mgmts)
        except:
            self._subnet_store.release(allocated_subnets)
            raise
        return conf