Doesn’t include, there being pages missing (6,3)

I believe the answer is:

leaves out

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'doesn't include there' is the definition.
I can't tell whether this defines the answer.

'pages missing' is the wordplay.
'pages' becomes 'leaves' (leaves can mean the pages of a book).
'missing' becomes 'out' (I've seen this in another clue).
'leaves'+'out'='LEAVES OUT'

'being' is the link.

Can you help me to learn more?

(Other definitions for leaves out that I've seen before include "Excludes" , "Overlooks" , "evidence that spring has arrived?" .)

I've seen this clue in the Evening Standard.

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