One's in the force? You'd hope not! (5)

I believe the answer is:

thief

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'you'd hope not' is the definition.
I can't tell whether this defines the answer.

'one's in the force?' is the wordplay.
'one' becomes 'I' (Roman numeral).
'in' is an insertion indicator.
'force?' becomes 'F' (symbol used in Physics e.g. f=ma).
'i' inserted into 'the' is 'thie'.
'thie'+'f'='THIEF'

Can you help me to learn more?

(Other definitions for thief that I've seen before include "Unlawful taker" , "Burglar, say" , "Person who steals things" , "Raffles, say" , "One who steals" .)

I've seen this clue in The Times.

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