With energy, Zulu reportedly, enters short country river? (7)

I believe the answer is:

zambezi

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'river?' is the definition.
(I know that Zambezi is a river)

I don't understand how the remainder of the clue works.

(Other definitions for zambezi that I've seen before include "River flowing into Indian Ocean northeast of Beira in Mozambique" , "River rising in Zambia" , "Maze biz (anag.); African river" , "African river, flows into the Indian Ocean" , "Central African river" .)

I've seen this clue in The Times.

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