Tradesman's entrance (4,7)

I believe the answer is:

shop doorway

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'tradesman's entrance' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'tradesman's entrance' is the wordplay.
'tradesman's' becomes 'shop' (I am not sure about this - if you are sure you should believe this answer much more).
'entrance' becomes 'doorway' (doorway is a kind of entrance).
'shop'+'doorway'='SHOP DOORWAY'

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I've seen this clue in The Globe and Mail.

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