code: def setKeepAliveTimeOut(self, iTimeOut):
          
          print '%s call setKeepAliveTimeOut' % self.port
          print iTimeOut
          try:
              cmd = WPANCTL_CMD + 'setprop NCP:SleepyPollInterval %s' % str(iTimeOut*1000)
              print cmd
              return self.__sendCommand(cmd)[0] != 'Fail'
          except Exception, e:
              ModuleHelper.WriteIntoDebugLogger('setKeepAliveTimeOut() Error: ' + str(e))
docs: set keep alive timeout for device
             has been deprecated and also set SED polling rate
  
          Args:
              iTimeOut: data poll period for sleepy end device
  
          Returns:
              True: successful to set the data poll period for SED
              False: fail to set the data poll period for SED