Challenges again from different setters (7)

I believe the answer is:

retests

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'challenges again' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'different setters' is the wordplay.
'different' indicates anagramming the letters (letters placed in a different order).
'setters' is an anagram of 'RETESTS'.

'from' acts as a link.

Can you help me to learn more?

(Other definitions for retests that I've seen before include "further examinations" , "Again investigates" .)

I've seen this clue in The Guardian.

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