[Pharo-users] [spec] set ballonText on a treeNode

Hi I think this is spec related. How can I set a ballonText on aTreeNode? I was expecting something like: tree childrenBlock: [ :anObject | self childrenFor: anObject ]; displayBlock: [ :anObject | self labelFor: anObject ]; helpBlock: [ :anObject | self helpFor: anObject ]; . but the last one is not available and I can not find something suitabe. How is the expected way? Best Emilio