📝 **Question:** Define \`flatten(items)\` that yields items from nested lists at any depth, using \`yield from\` for recursion. Run on \`[1, [2, [3, 4]], 5]\` and print each item on its own line.\nExpected:\n1\n2\n3\n4\n5 📋 Pick the right answer. 💡 **Hint:** Re-read the theory above if unsure.