let jpeg = UTI("public.jpeg")

let jpeg = UTI(filenameExtension: "jpeg")

let jpeg = UTI(mimeType: "image/jpeg")

UTI(mimeType: "image/jpeg").filenameExtensions // => ["jpeg", "jpg", "jpe"]

UTI(filenameExtension: "jpeg").mimeTypes // => ["image/jpeg"]

UTI(mimeType: "image/jpeg") == UTI(filenameExtension: "jpeg") // => true

switch UTI(kUTTypeJPEG) {
case UTI(kUTTypeImage):
    print("JPEG is a kind of images")
default:
    fatalError("JPEG must be a image")
}