Right usurps Left in Black Death City (6)

I believe the answer is:

prague

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'city' is the definition.
(Prague is an example)

I cannot understand how the rest of the clue works.

(Other definitions for prague that I've seen before include "Gear up for this European city" , "European capital" , "Rather quiet" , "Capital city of Czech Republic" , "Czech Republic's capital" .)

I've seen this clue in The Sun.

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