Modern container made to go by elephant (9,3)

I believe the answer is:

polythene bag

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'modern container made' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'go by elephant' is the wordplay.
'go by elephant' can be anagrammed to 'POLYTHENE BAG'.
However, I am not clear how this is indicated.

'to' is the link.

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I've seen this clue in The Globe and Mail.

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