"Impossible!"

There are a few possibilities for this:

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6 7

2-2

10*

no-go

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

This is all the clue.

(Other definitions for no-go that I've seen before include "Can't be done, not on" , "Hopeless (informal)" , "Area forbidden to certain groups, maybe police" , "Prohibited area" , "Impossible task for goon" .)

I've seen this clue in The Guardian.

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