filter one columns data based on other column's value
filter one columns data based on other column's value

I've search most posts in forum and find that all the filter are based on the value of itself.
let's say I have a table with 2 columns:
col-1 col-2
A 1
A 2
A 3
A 4
B 1
B 2
C 1
D 1
Can I filter col-2 data based on col-1 value? for example, get [1,2,3,4] for A?
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