Is there a way to map drop down list items when using Custom API?

I am using Xano as my backend. I have a simple country drop-down list that I populate from Xano. Xano provides both a 3-character code and country name from the Backend Query. I have set the drop-down list "define options" to use the API call list from the Backend Query.

Since I am using a custom API, I need to select JSON Body, JSON Path and complete the JSON path name. Then when I select "Available Options", there is no option for "map list item"?

The "map list item" is an option when using a Firebase DB.
https://docs.flutterflow.io/widgets-and-components/widgets/form-elements-1/dropdown#showing-options-from-firestore-data

You can also set option labels if you manually set the drop-down list items.
https://docs.flutterflow.io/widgets-and-components/widgets/form-elements-1/dropdown#showing-option-label

Is there no way to do this when using a custom API to populate the drop-down list? If the answer is no, what is the best workaround? Hopefully, the only answer is not manually creating the "drop-down list items" as there are over 200 countries!

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