def _parse_annotation_coords(ff, coords, xy):
    """ Convert a coordinate name and xy into a tikz coordinate string """
    if coords == 'data':
        x, y = xy
        return f'(axis cs:{x:{ff}},{y:{ff}})'
    elif coords == 'figure points':
        raise NotImplementedError
    elif coords == 'figure pixels':
        raise NotImplementedError
    elif coords == 'figure fraction':
        raise NotImplementedError
    elif coords == 'axes points':
        raise NotImplementedError
    elif coords == 'axes pixels':
        raise NotImplementedError
    elif coords == 'axes fraction':
        raise NotImplementedError
    elif coords == 'data':
        raise NotImplementedError
    elif coords == 'polar':
        raise NotImplementedError
    else:
        raise NotImplementedError
