class AVLNode:
    def __init__(self, data, left=None, right=None, height=-1):
        self.data=data
        self.left=left
        self.right=right
        self.height=height
        self.firstKey=data.B
        self.secondKey=node.data.H
        nnode=node.data.order.copy()
        nnode[self.firstKey]=0
        self.thirdKey=nnode