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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 add_lb_secgroup(self, lb_name, hosts, port):
 """ Used by the load balancer deployer to register a hostname for a load balancer, in order that security group rules can be applied later. This is multiprocess-safe, but since keys are accessed only be a single load balancer deployer there should be no conflicts. :param str lb_name: The load balancer name (as per the config file) :param :class:`list` hosts: The load balancer host[s], once known :param port: The backend port that the LB will connect on """

        self.lb_sec_groups.merge(lb_name, {'hosts': hosts, 'port': port})