- sphinx requires titles to build docs.
- the code follows:
```
import os

for root, dirs, files in os.walk("source", topdown=False):
    if "README.md" not in files:
        continue

    path = os.path.join(root, "README.md")
    print(path)
    with open(path) as f:
        content = f.read()

    if "# " not in content:
        with open(path, "w") as f:
            f.write(f"# {root.split('/')[-1]}\n" + content)
```