Get shot of rotten cargo (7)

I believe the answer is:

offload

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'get shot' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'rotten cargo' is the wordplay.
'rotten' becomes 'off' (rotten food is 'off').
'cargo' becomes 'load' (synonyms).
'off'+'load'='OFFLOAD'

'of' acts as a link.

Can you help me to learn more?

(Other definitions for offload that I've seen before include "Get rid of (unwanted item or burden)" , "Dump" , "9 [JETTISON]" , "deliver goods" .)

I've seen this clue in The Telegraph.

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