VideoCapture serial id

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As well is known, the VideoCapture recognises the device id as the cameras are connected. For example, if I have a webcam and two cameras, the devices would be 1,2 and 3 (maybe). But what I wanna know how to get unique identificators per camera. I mean, if I connect the cameras in another way in the future, the device id would be changed as 1,3 and 2. But I don't want that, I want the devices to have unique serial identificators for saving captured data and stuff from the concrete camera.

So, how can I get the "serial id" or "unique id" for each camera?

Thanks in advance