A biscuit or photo? It’s the same thing! (4)

I believe the answer is:

snap

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'a biscuit' is the definition.
(I know that snap is a type of biscuit)

I don't understand the rest of the clue.

(Other definitions for snap that I've seen before include "Speak irritably; break" , "game of cards" , "Unpremeditated - bite" , "Break; bite suddenly" , "piece of cake" .)

I've seen this clue in The Times.

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