machine-id.py

def _get_machine_id():
    """Return the machine-id UUID."""
    with open('/etc/machine-id', 'r') as f:
        # The machine ID is a single newline-terminated, hexadecimal,
        # 32-character, lowercase ID.
        machine_id_int = int(f.read().strip(), 16)
        machine_id_bytes = bytearray(machine_id_int.to_bytes(16, 'big'))
        # see manpage machine-id(5)
        machine_id_bytes[6] = (machine_id_bytes[6] & 0x0F) | 0x40
        machine_id_bytes[8] = (machine_id_bytes[8] & 0x3F) | 0x80
        machine_uuid = uuid.UUID(bytes=bytes(machine_id_bytes))
        return str(machine_uuid)