How to use multiple video assets in this code example.

[VarinderSH]

let context = try! MTIContext(device: MTLCreateSystemDefaultDevice()!)
let handler = MTIAsyncVideoCompositionRequestHandler(context: context, tracks: asset.tracks(withMediaType: .video)) { request in
return FilterGraph.makeImage { output in
request.anySourceImage => filterA => filterB => output
}!
}
let composition = VideoComposition(propertiesOf: asset, compositionRequestHandler: handler.handle(request:))
let playerItem = AVPlayerItem(asset: asset)
playerItem.videoComposition = composition.makeAVVideoComposition()
player.replaceCurrentItem(with: playerItem)
player.play()