Holds good bastion in the wars (7)

I believe the answer is:

obtains

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'holds' is the definition.
('obtain' can be a synonym of 'hold')

'good bastion in the wars' is the wordplay.
'bastion' anagrams to 'OBTAINS'.
However, I am not clear how this is indicated.

Can you help me to learn more?

(Other definitions for obtains that I've seen before include "Authority" , "Gets" .)

I've seen this clue in The Times.

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