I got it working.
It would be interesting to know the error I made
Perldoc said:

remove([list]) Remove objects from a Set::Object. Removing the same object more than once, or removing an object absent from the Set::Object is not an error. Returns the number of elements that were actually removed.

So I try to use the method

remove($array_ref)

Actually what required was

 
 remove(@array_or_list)
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artist