Wake up cooler? (4)

I believe the answer is:

stir

I believe this clue is a double definition.

'wake up' is the first definition.
(I've seen this in another clue)

'cooler?' is the second definition.
(both are slang terms for prison)

(Other definitions for stir that I've seen before include "Whisk, agitate" , "Mix the ingredients" , "Mix round" , "Stimulate; prison" , "can > go forth" .)

I've seen this clue in The Telegraph and The Globe and Mail.

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