def add_rotation(im, ccw_rotation_degrees: int=90):
    """Rotate an image CCW by `ccw_rotation_degrees` degrees.

    :param im: input image
    :type im: PIL image object
    :param ccw_rotation_degrees: number of degrees to rotate counter-clockwise
    :type ccw_rotation_degrees: int
    :return: rotated image
    :rtype: PIL image object
    """
    return im.rotate(ccw_rotation_degrees, expand=True)
