Artless; gullible (5)

I believe the answer is:

naive

I believe this clue is a double definition.

'artless' is the first definition.
(similar in meaning)

'gullible' is the second definition.
(similar in meaning)

(Other definitions for naive that I've seen before include "Short on experience" , "Innocently trustful" , "childlike" , "Lacking wisdom and judgement" , "Jejune" .)

I've seen this clue in The Guardian.

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