Book help for musician (7)

I believe the answer is:

bassist

'for musician' is the definition.
(bass guitarist)

'book help' is the wordplay.
'book' becomes 'b' (abbreviation for book).
'help' becomes 'assist' (to assist someone is to help them).
'b'+'assist'='BASSIST'

(Other definitions for bassist that I've seen before include "Musician" , "jazz player" .)

I've seen this clue in The Telegraph.

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