List of all Tree Children

Hello,

yesterday I asked for some advice on writing a function which retrieves all children of a tree which do not have children themselves. Here a function I wrote. Maybe it is useful to somebody.
peter

     def AddChildToList(self,item,liste):
         if self.tree.ItemHasChildren(item):
             cookie = 1
             child,cookie = self.tree.GetFirstChild(item, cookie)
             last = self.tree.GetLastChild(item)
             while child != last:
                 liste = self.AddChildToList(child,liste)
                 child = self.tree.GetNextSibling(child)
             liste = self.AddChildToList(last,liste)
         else:
             liste.append(item)
         return liste