utility function for updating a node
def UpdateUtil ( x : node ) -> node : NEW_LINE INDENT x . l0 , x . l1 = x . l1 , x . l0 NEW_LINE x . r0 , x . r1 = x . r1 , x . r0 NEW_LINE x . min1 , x . min0 = x . min0 , x . min1 NEW_LINE x . max0 , x . max1 = x . max1 , x . max0 NEW_LINE return x NEW_LINE DEDENT