📝 **Task:** Complete the function. Use the provided skeleton: \`download(url)\` should increment \`stats["ok"]\` under the lock and return \`f"got {url}"\`. Then run it on \`["a", "b", "c"]\` with a ThreadPoolExecutor(max_workers=3) and finally print \`stats["ok"]\`.\nExpected: 3 📋 Edit the starter code below. Tests run automatically. 💡 **Hint:** Re-read the theory if you get stuck.