'Power on / power off / get power status /reboot a system.
@param str system Cobbler system
@param str power_operation power operation. Valid values: on, off, reboot, status
@param str token Cobbler authentication token
@param str user power management user
@param str password power management password
@param Logger logger logger
@return bool if operation was successful'

def power_system(self, system, power_operation, user=None, password=None, logger=None):

    if (power_operation == 'on'):
        self.power_mgr.power_on(system, user=user, password=password, logger=logger)
    elif (power_operation == 'off'):
        self.power_mgr.power_off(system, user=user, password=password, logger=logger)
    elif (power_operation == 'status'):
        self.power_mgr.get_power_status(system, user=user, password=password, logger=logger)
    elif (power_operation == 'reboot'):
        self.power_mgr.reboot(system, user=user, password=password, logger=logger)
    else:
        utils.die(self.logger, ("invalid    power    operation    '%s',    expected    on/off/status/reboot" % power_operation))
