iOS8 Photos Framework: How to get the name(or filename) of a PHAsset?

I know the question has already been answered, but I figured I would provide another option:

extension PHAsset {
    var originalFilename: String? {
        var fileName: String?

        if #available(iOS 9.0, *) {
            let resources = PHAssetResource.assetResources(for: self)
            if let resource = resources.first {
                fileName = resource.originalFilename
            }
        }

        if fileName == nil {
            /// This is an undocumented workaround that works as of iOS 9.1
            fileName = self.value(forKey: "filename") as? String
        }

        return fileName
    }
}