Copy Roman numerals (5)

I believe the answer is:

mimic

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'copy' is the definition.
(I know that mimic is a type of copy)

I cannot understand how the rest of the clue works.

(Other definitions for mimic that I've seen before include "Act like" , "Impressionist" , "Appear just like" , "'Copy, imitate (5)'" , "Go round a bend (in car)" .)

I've seen this clue in the Evening Standard.

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