What the solution suggests for problem 10, still fails for me with an error. <img width="968" alt="image" src="https://user-images.githubusercontent.com/55892116/195750339-76c93c3b-3eeb-4351-94a3-9a740e2c2e66.png"> <img width="849" alt="image" src="https://user-images.githubusercontent.com/55892116/195750611-ae1951db-fbbb-4bc5-ba37-28f5234a5d94.png"> **But adding the Set<string> in the variable type itself works:** <img width="691" alt="image" src="https://user-images.githubusercontent.com/55892116/195750887-41d7bc71-4bb6-48b0-b3f9-03886ec51167.png"> <img width="588" alt="image" src="https://user-images.githubusercontent.com/55892116/195750910-877e7544-391f-48cf-8983-2324d5cf10ae.png"> I don't really understand the issue, but if you want I could open a PR which fixes the test :)