How to get iCloud item(photo/video) size?

How I can get iCloud photo file size? Could I use private API like this in prod? Does anyone know another way? (without downloading the file to the device)

func getFileSize(asset: PHAsset) -> Int64? {
    let resources = PHAssetResource.assetResources(for: asset)
    let resource = resources.first 
     let size = resource?.value(forKey: "fileSize") as? Int64
     return size
}
How to get iCloud item(photo/video) size?
 
 
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