Invalid syntax error appears. Helping beginners.

I hurt myself with the part in the book, but when I first put the Returns part on the left wall, I got an error called expected an indented block, so I wrote it with a space But I got this error message from none. What should I do? Please let me know. I'd appreciate it if you could tell me in detail It's so frustrating Help a beginner I think the none part is wrong, but if it pops up in orange like that, didn't you hit it right? For your information, I indented more returns and corrected the error