Prisoners into this, a good pandowdy prepared on the outside? (5,5)

I believe the answer is:

paddy wagon

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'prisoners into this' is the definition.
The definition suggests a singular noun which matches the answer.

'a good pandowdy prepared on the outside?' is the wordplay.
'good' becomes 'g' (abbreviation).
'prepared' indicates anagramming the letters.
'on the outside?' is an insertion indicator.
'pandowdy' anagrammed gives 'paddywon'.
'a'+'g'='ag'
'ag' put inside 'paddywon' is 'PADDY-WAGON'.

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I've seen this clue in The Independent.

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