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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_chassis(self, chassis, port=22611, password='xena'):
 """ Add chassis. XenaManager-2G -> Add Chassis. :param chassis: chassis IP address :param port: chassis port number :param password: chassis password :return: newly created chassis :rtype: xenamanager.xena_app.XenaChassis """


        if chassis not in self.chassis_list:
            try:
                XenaChassis(self, chassis, port, password)
            except Exception as error:
                self.objects.pop('{}/{}'.format(self.owner, chassis))
                raise error
        return self.chassis_list[chassis]