Small function to use torch

TorchFunction.swift

    func setTorch(on: Bool) {
        guard let device = AVCaptureDevice.default(for: AVMediaType.video),
                  device.hasTorch else {
            return
        }

        do {
            try device.lockForConfiguration()

            if on {
                do {
                    try device.setTorchModeOn(level: 1.0)
                } catch {
                    print(error)
                }
            } else {
                device.torchMode = AVCaptureDevice.TorchMode.off
            }

            device.unlockForConfiguration()
        } catch {
            print(error)
        }
    }