Fix alley worker once (3,6)

I believe the answer is:

pin setter

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'fix alley worker once' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'fix alley worker once' is the wordplay.
'fix' becomes 'pin' (to pin is to fix in place).
'alley worker once' becomes 'setter' (I've seen this in another clue).
'pin'+'setter'='PIN SETTER'

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I've seen this clue in the Sydney Morning Herald.

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