Pleasant surprise in Streatham (5)

I believe the answer is:

treat

'pleasant surprise' is the definition.
(I've seen this before)

'in streatham' is the wordplay.
'in' says the answer is hidden in the clue.
'TREAT' can be found hidden inside 'streatham'.

(Other definitions for treat that I've seen before include "Try to heal" , "could be a feast" , "Celebration" , "Doctor, manage" , "Enjoyable party" .)

I've seen this clue in The Sun.

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