def sample_to_plane(sample_orientation: str):
    """Return a Cartesian circle plane type for a given sample orienation type"""
    sample_to_plane = {'S1': 'YZ', 'S2': 'XZ', 'S3': 'XY', 
                       'S1R': 'ZY', 'S2R': 'ZX', 'S3R': 'YX', 
                       'S4': 'YX to YZ', 'S5': 'XY to XZ', 'S6': 'XZ to YZ'}
    plane = sample_to_plane[sample_orientation]
    return plane