def _describe_fs_path_for_checksum(path):
    # This is not entirely correct as it does not detect changes for
    # contents from alternatives.  However for the moment it's good
    # enough.
    if os.path.isfile(path):
        return b'\x01'
    if os.path.isfile(os.path.join(path, 'contents.lr')):
        return b'\x02'
    if os.path.isdir(path):
        return b'\x03'
    return b'\x00'
Given a file system path this returns a basic description of what
dataset/ETHPy150Open lektor/lektor/lektor/builder.py/_describe_fs_path_for_checksum