Knock out article on city and tolerate marsupial (5,4)

I believe the answer is:

koala bear

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'marsupial' is the definition.
(koala bear is a kind of marsupial)

'knock out article on city and tolerate' is the wordplay.
'knock out' becomes 'ko'.
'article on' becomes 'a' (the indefinite article in English. I am not sure about the 'on' bit.).
'city' becomes 'LA' (Los Angeles).
'and' means one lot of letters go next to another.
'tolerate' becomes 'bear' (synonyms).
'ko'+'a'+'la'+'bear'='KOALA BEAR'

Can you help me to learn more?

(Other definitions for koala bear that I've seen before include "Eucalyptus eater" , "Creature" , "Australian animal" , "Aussie tree-hugger" , "Australian arboreal marsupial" .)

I've seen this clue in The Daily Express.

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