Ready for action, his own epitaph prepared (4,4,5)

I believe the answer is:

whip into shape

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'ready for action' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'his own epitaph prepared' is the wordplay.
'prepared' indicates an anagram.
'his'+'own'+'epitaph'='hisownepitaph'
'hisownepitaph' with letters rearranged gives 'WHIP INTO SHAPE'.

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(Other definitions for whip into shape that I've seen before include "Prepare for action" , "Bring forcefully to the desired state" , "Forcefully bring to proper condition" .)

I've seen this clue in The Telegraph.

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