A temp in some hole-in-the-wall job? (4-3)

I believe the answer is:

stop-gap

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'a temp in some hole-in-the-wall job?' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'a temp in some hole' is the wordplay.
'a temp in' becomes 'stop' (I am not sure about this - if you are sure you should believe this answer much more).
'some hole' becomes 'gap'.
'stop'+'gap'='STOP-GAP'

Can you help me to learn more?

I've seen this clue in the Evening Standard.

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