code: func findVirtualDeviceInListDeviceSelectFunc(ckey int32, du int) func(types.BaseVirtualDevice) bool {
  	return func(d types.BaseVirtualDevice) bool {
  		vd := d.GetVirtualDevice()
  		if vd.ControllerKey == ckey && vd.UnitNumber != nil && *vd.UnitNumber == int32(du) {
  			return true
  		}
  		return false
  	}
  }
docs: // findVirtualDeviceInListDeviceSelectFunc returns a function that can be used
  // with VirtualDeviceList.Select to locate a virtual device based on its
  // controller device key, and the unit number on the device.