Drawing a box with a hole in it (7)

I believe the answer is:

cartoon

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'drawing' is the definition.
(type of drawing)

I cannot understand how the remainder of the clue works.

(Other definitions for cartoon that I've seen before include "eg 'The Simpsons'" , "One may find it funny" , "Humorous or satirical drawing" , "Witty drawing" , "Humorous drawing or film of a succession of them" .)

I've seen this clue in the Evening Standard.

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