Python：将元组转换为列表并插入（） - 在一个表达式中？

Question

I am trying to do something like this:

my_list = list((1,2,3)).insert(0,0)

Is there a way to do that in one expression?

PS I am not trying to be economic with my lines, I'm just curious is that possible and how would one do it in python.

Answer 1

If you are on python 3.8+ this is doable

>>> (my_list:=list((1,2,3))).insert(0,0)
>>> my_list
[0, 1, 2, 3]

Answer 2

One slightly naive way is the following:

a = [0] + list((1,2,3))

.insert() (same as .append() , .extend() , etc) modifies the list but don't actually return anything, that's why you can't use them in a chained operation. See the answer here about why this happens as a Python design choice.