Since backpacks contain links to vehicles they've been assembled to (drones and static weapons), it would be useful to have a scripting command that returns that link. You can already check if vehicle is packed into backpack with objectParent, so its only natural to have command that works
Suggested syntax:
getBackpackVehicle ENTITY, takes backpack entity, returns the vehicle it assembles to or null of it wasn't assembled once yet or invalid\can't assemble