Basically, but not quite. :-) The original result for b is: 0, (1, [...]), 2, 3] vs your version: [0, [...], 2, 3] The equivalent statements to the orig

Basically, but not quite. :-) The original result for b is: 0, (1, [...]), 2, 3] vs your version: [0, [...], 2, 3] The equivalent statements to the original chained assignment are: a, b = 1, [0, 1, 2, 3] b[a] = 1, b # relies on cpython implementation detail¹ ¹: Using 1 works because the integers -5 thru 256 are interned in cpython. Otherwise, or if you don't want to rely on an implementation detail, to be truly equivalent (i.e. `id(b[1][0]) == id(a)`), it's this: a, b = 1, [0, 1, 2, 3] b[a] = a, b