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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 _update_redundancy_router_interfaces(self, context, router, port, modified_port_data, redundancy_router_ids=None, ha_settings_db=None):
 """To be called when the router interfaces are updated, like in the case of change in port admin_state_up status """

        router_id = router['id']
        if ha_settings_db is None:
            ha_settings_db = self._get_ha_settings_by_router_id(context,
                                                                router_id)
        if ha_settings_db is None:
            return
        e_context = context.elevated()

        rr_ids = self._get_redundancy_router_ids(e_context, router_id)
        port_info_list = self._core_plugin.get_ports(
            e_context, filters={'device_id': rr_ids,
                                'network_id': [port['network_id']]},
            fields=['device_id', 'id'])
        for port_info in port_info_list:
            self._core_plugin.update_port(e_context, port_info['id'],
                                          modified_port_data)
        self._update_hidden_port(e_context, port['id'], modified_port_data)