Is there a way to subtract 3 from every digit of a number?

[C W]

Hello everyone,

I'm curious if there is a way take number and back each digit by 3 ?

2342 becomes 9019
8475 becomes 5142
5873 becomes 2540

The tricky part is that 2 becomes 9, not -1.

Here's my toy example and what I attempted,
> test_series = pd.Series(list(['2342', '8475', '5873']))
> test_series
0    2342
1    8475
2    5873
dtype: object

> test_series.str.split('')
[, 2, 3, 4, 2, ]
[, 8, 4, 7, 5, ]
[, 5, 8, 7, 3, ]
dtype: object

What a good approach to this? Is there a method or function that should be
handling this?

Thanks so much!

Mike