DriveApp未定义

Question

DriveApp未定义虽然我已经在页面中声明了脚本但仍然看到相同的内容。

    function moveFolderToFolder(sourceFolderId, targetFolderId) {
     var targetFolder = DriveApp.getFolderById(targetFolderId);
     var sourceFolder = DriveApp.getFolderById(sourceFolderId);
     var currentFolders = sourceFolder.getParents();
     while (currentFolders.hasNext()) {
       var currentFolder = currentFolders.next();
       currentFolder.removeFolder(sourceFolder);
     }
     targetFolder.addFolder(sourceFolder);
}

请帮我解决这个问题。