def identify(rod, x, y):
    """Adds chip ids (chip_x, chip_y) to the key for a rod

    Args:
        rod: dict of (x, y): [values]
        x: x coordinate that identifies the source chip
        y: y coordinate that identifies the source chip
        
    Returns:
        dict: {(chip_x, chip_y, x, y): [values]}
    """

    return {(x, y, k[0], k[1]): v for k, v in rod.items()}