def __init__(self, max_deg, interp=cv2.INTER_LINEAR, step_deg=None):
        """
        Args:
            max_deg, interp, step_deg: same as :class:`Rotation`
        """
        assert step_deg is None or (max_deg == 180 and max_deg % step_deg == 0)
        super(RotationAndCropValid, self).__init__()
        self._init(locals())

        Args:
            max_deg, interp, step_deg: same as :class:`Rotation`
        
tensorpack/dataflow/imgaug/geometry.py