He peeks first to be up on things (3)

I believe the answer is:

hep

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'to be up on things' is the definition.
I can't judge whether this definition defines the answer.

'he peeks first' is the wordplay.
'peeks first' becomes 'p' (1st letter of 'peeks').
'he'+'p'='HEP'

Can you help me to learn more?

(Another definition for hep that I've seen is " Knowing (jazz slang); rhymes with dance move".)

I've seen this clue in the Sydney Morning Herald.

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