PM with brown ale dancing in nude (6,5,3)

I believe the answer is:

andrew bonar law

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'nude' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'pm with brown ale dancing in' is the wordplay.
'pm' becomes 'andra' (I can't justify this - if you can you should believe this answer much more).
'with' becomes 'w' (short for with).
'dancing' indicates an anagram.
'in' indicates putting letters inside.
'brown'+'ale'='brownale'
'brownale' with letters rearranged gives 'ewbonarl'.
'andra'+'w'='andraw'
'andraw' placed around 'ewbonarl' is 'ANDREW BONAR LAW'.

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I've seen this clue in The Guardian.

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