"Up yours!" - brute pinching book (3-3)

I believe the answer is:

yah-boo

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'up yours' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'brute pinching book' is the wordplay.
'brute' becomes 'yahoo' (I've seen this before).
'pinching' means one lot of letters goes inside another (taking inside).
'book' becomes 'b' (abbreviation for book).
'yahoo' enclosing 'b' is 'YAH-BOO'.

Can you help me to learn more?

(Another definition for yah-boo that I've seen is " Derisive exclamation".)

I've seen this clue in The Independent.

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