He put in shift, angry and agitated (5)

I believe the answer is:

hetup

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'angry and agitated' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'he put in shift' is the wordplay.
'in shift' indicates an anagram (I've seen this in other clues).
'put' is an anagram of 'tup'.
'he'+'tup'='HETUP'

Can you help me to learn more?

(Another definition for hetup that I've seen is " Angry".)

I've seen this clue in The Irish Times.

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