<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _plumb_port(self, server, network_id, wrong_ips):
 """Look for an existing port on the network Add one if it doesn't exist """


        for attached_interface in server.interface_list():
            if attached_interface.net_id == network_id:
                if any(map(lambda x: x['ip_address'] in wrong_ips, attached_interface.fixed_ips)):
                    continue
                return attached_interface

        return server.interface_attach(None, network_id, None)