Got the snake trapped? That's capital! (6)

I believe the answer is:

bogota

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'that's capital' is the definition.
(Bogota is an example)

I don't understand the rest of the clue.

(Other definitions for bogota that I've seen before include "Capital city of Colombia" , "Andean city" , "Tobago in South America" , "Colombian capital" , "Colombian city" .)

I've seen this clue in the Evening Standard.

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