Not long tunes I'm composing (7)

I believe the answer is:

minutes

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'not long tunes i'm composing' is the definition.
I can't tell whether this defines the answer.

'tunes i'm composing' is the wordplay.
'composing' indicates anagramming the letters.
'tunes'+'im'='tunesim'
'tunesim' anagrammed gives 'MINUTES'.

Can you help me to learn more?

(Other definitions for minutes that I've seen before include "Records" , "summary" , "Units of time" , "Recorded notes of a meeting" , "Written account of a meeting" .)

I've seen this clue in The Sun.

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