A prickly sort shocked Rt Hon. ex-president (9)

I believe the answer is:

thornbush

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'a prickly sort' is the definition.
I know nothing about this answer so I can't tell whether this works.

'shocked rt hon ex-president' is the wordplay.
'shocked' indicates anagramming the letters (letters are shocked or disrupted).
'ex-president' becomes 'Bush' (either of the George Bushes).
'rt'+'hon'='rthon'
'rthon' with letters rearranged gives 'thorn'.
'thorn'+'bush'='THORNBUSH'

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I've seen this clue in The Telegraph.

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