def get_config_file() -> Optional[Path]:
    """
    Looks for a .env file in current folder or its parents. Returns Path of
    found .env or None if not found.
    """
    for path in [Path().cwd(), *Path.cwd().parents]:
        file = path / ".env"
        if file.exists():
            return file

    return None

    Looks for a .env file in current folder or its parents. Returns Path of
    found .env or None if not found.
    
src/core/trulens/core/utils/keys.py