how to develop carkey?

With the release of IOS 14, it is said that the iPhone can use the carkey framework as the car key, but there is no valuable API introduction at present. If we want to develop the carkey, is it based on the API developed by Apple or requires the manufacturer to cooperate with apple? I hope someone can answer my question.
Digital car keys will be developed by automakers. You can learn more about car keys in tomorrow's WWDC20 session Introducing Car Keys.
how to develop carkey?
 
 
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