'Turn the device off.'

def _turn_off_main(self, value_type=None, value=None):

    set_req = self.gateway.const.SetReq
    if ((value_type is None) or (value is None)):
        _LOGGER.warning('%s:    value_type    %s,    value    =    %s,    None    is    not    valid    argument    when    setting    child    value', self._name, value_type, value)
        return
    self.gateway.set_child_value(self.node_id, self.child_id, value_type, value)
    if self.gateway.optimistic:
        self._state = False
        self._values[value_type] = (STATE_OFF if (set_req.V_LIGHT in self._values) else value)
        self.schedule_update_ha_state()
