Awful old bat! A really nasty person (3,3)

I believe the answer is:

bad lot

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'a really nasty person' is the definition.
I know that 'person' relates to this answer.

'awful old bat' is the wordplay.
'awful' indicates anagramming the letters.
'old'+'bat'='oldbat'
'oldbat' with letters rearranged gives 'BAD LOT'.

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(Other definitions for bad lot that I've seen before include "Crook" , "Person of depraved character" , "Thoroughly unreliable person" , "Rotten fellow" , "Disreputable person" .)

I've seen this clue in the Evening Standard.

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