Make a picture, forswearing a beer (4)

I believe the answer is:

pint

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'beer' is the definition.
(beer is typically served by the pint)

I can't explain the remainder of the clue.

(Other definitions for pint that I've seen before include "Liquid measure" , "The working man's drink measure" , "Unit of capacity" , "Glass of beer (colloq.)" , "Liquid meassure - four gills" .)

I've seen this clue in The Times.

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