Appropriate assertion of modernist poet? (7)

I believe the answer is:

impound

I believe this is a double definition.

'appropriate' is the first definition.
(appropriate can mean to take or impound)

'assertion of modernist poet?' is the second definition.
(Ezra Pound might have said 'I'm Pound')

(Other definitions for impound that I've seen before include "Seize and confine (illegal vehicle)" , "Sequester" , "Seize and take into legal custody" , "put cordon round" , "Seize (goods) legally" .)

I've seen this clue in The Independent.

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