private function _mapByTreeDepthDesc($tree)
 {
     $req = new DownlineMapTreeByDepthRequest();
     $req->setDataToMap($tree);
     $req->setAsCustomerId(Compress::ATTR_CUSTOMER_ID);
     $req->setAsDepth(Snap::ATTR_DEPTH);
     $req->setShouldReversed(true);
     $resp = $this->_callDownlineMap->treeByDepth($req);
     return $resp->getMapped();
 }