# python 單行賦值(swap) ```python= cur.next, prev, cur = prev, cur, cur.next ``` see the exmaple ![](https://i.imgur.com/tDWubHb.png) 原理： In simple terms, it pushes the values of a and b on the stack, rotates (swaps) the top two elements, then pops the values again. See also: Python Bytecode Instructions.