NSAttributedStringKey giving an unresolved identifier error

Question

I\'m following an online tutorial to build a magazine type iOS application. I\'m attempting to use NSAttributedStringKey but keep getting the error shown below. Any ideas?

Answer 1

The projects are probably in different versions of Swift.

In Swift 4, NSFontAttributeName has been replaced with NSAttributedStringKey.font.

as stated here NSFontAttributeName vs NSAttributedStringKey.font

Need to confirm whether it will work on versions less than ios11