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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 _select_mgmt_networks(self, conf):
 """ Select management networks. If no management network is found, it will mark the first network found by sorted the network lists. Also adding default DNS domain, if none is set. Args: conf(spec):
 spec """


        nets = conf['nets']
        mgmts = sorted(
            [
                name for name, net in nets.iteritems()
                if net.get('management') is True
            ]
        )

        if len(mgmts) == 0:
            mgmt_name = sorted((nets.keys()))[0]
            LOGGER.debug(
                'No management network configured, selecting network %s',
                mgmt_name
            )
            nets[mgmt_name]['management'] = True
            mgmts.append(mgmt_name)

        for mgmt_name in mgmts:
            if nets[mgmt_name].get('dns_domain_name', None) is None:
                nets[mgmt_name]['dns_domain_name'] = 'lago.local'

        return mgmts