Gets the id of some associated asset.
It may be the case that the object has no set asset, or even that such an asset does not yet exist in the GES cache. Instead, this will return the asset id that is _compatible_ with the current state of the object, as determined by the Extractable implementer. If it was indeed extracted from an asset, this should return the same as its corresponding asset id.
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The id of some associated Asset that is compatible with this's current state. |