Dukes aren't given to breaking promises (10)

I believe the answer is:

undertakes

'promises' is the definition.
(undertaking is a kind of promising)

'dukes aren't given to breaking' is the wordplay.
'given to' is a charade indicator (letters next to each other).
'breaking' indicates an anagram.
'dukes'+'arent'='dukesarent'
'dukesarent' with letters rearranged gives 'UNDERTAKES'.

I've seen this clue in The Globe and Mail.

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