Poem seen as arcane incantation (4,6)

I believe the answer is:

open sesame

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'incantation' is the definition.
(thesaurus)

'poem seen as arcane' is the wordplay.
'poem seen as' anagrams to 'OPEN SESAME'.
But, I am not sure how this is indicated.

Can you help me to learn more?

(Other definitions for open sesame that I've seen before include "Magical words" , "Words of Ali Baba" , "a very successful means of achieving a result" , "door-unlocking spell" , "free entry" .)

I've seen this clue in The Independent.

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