Such a story is not a tall one (5)

I believe the answer is:

short

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'such a story' is the definition.
(short story is a kind of story)

I cannot understand how the rest of the clue works.

(Other definitions for short that I've seen before include "Having little length" , "Uncivil, brief film" , "Of small duration" , "Not long enough" , "Limited in duration" .)

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