Number of cops that carry guns? (4,3,3)

I believe the answer is:

nine one one

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'carry guns?' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'number of cops' is the wordplay.
'number' becomes 'nine' (nine is a number).
'of cops' becomes 'oneone' (I can't explain this - if you can you should believe this answer much more).
'nine'+'oneone'='NINE ONE ONE'

'that' is the link.

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