Ditzy type can test briar, surprisingly (12)

I believe the answer is:

scatterbrain

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'ditzy type' is the definition.
I can't tell whether this defines the answer.

'can test briar surprisingly' is the wordplay.
'surprisingly' is an anagram indicator.
'can'+'test'+'briar'='cantestbriar'
'cantestbriar' with letters rearranged gives 'SCATTERBRAIN'.

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(Other definitions for scatterbrain that I've seen before include "Person incapable of concentration" , "I'll forget" , "Disorganised thinker" , "One who cannot concentrate" , "Dippy type" .)

I've seen this clue in The Times.

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