A canny sort unexpectedly becoming pioneering MP (5,5)

I believe the answer is:

nancy astor

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'pioneering mp' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'a canny sort unexpectedly' is the wordplay.
'unexpectedly' indicates an anagram.
'a'+'canny'+'sort'='acannysort'
'acannysort' with letters rearranged gives 'NANCY ASTOR'.

'becoming' is the link.

Can you help me to learn more?

(Another definition for nancy astor that I've seen is " First woman to sit in the British House of Commons".)

I've seen this clue in The Times.

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