move up in a treeview in tkinter

I have found this function shown below very useful to move down in a treeview, but I ask here if there is a move up function.

def moveDown(self):
    curSelection = self.tree.selection() # current row - from /68508694/
    nextSelection = self.tree.next(curSelection) # next row
    self.tree.selection_set(nextSelection) # set the next row to be the current row
    self.tree.see(nextSelection) # make sure the current row is shown - from /10155153/

Thank