Made pun, as well, when it's cut and dried (3,4,2)

I believe the answer is:

all sewn up

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'it's cut and dried' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'made pun as well' is the wordplay.
'made' indicates anagramming the letters.
'pun'+'as'+'well'='punaswell'
'punaswell' with letters rearranged gives 'ALL SEWN UP'.

'when' acts as a link.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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