def METHOD_NAME(self, x, y):
    """Maps the (x,y) pixel coordinates of the image into the system coordinates.
    :param x: pixel coordinate (can be 1d numpy array), defined in the center of the
        pixel
    :param y: pixel coordinate (can be 1d numpy array), defined in the center of the
        pixel
    :return: relative (RA, DEC) coordinates of the system
    """
    return util.map_coord2pix(
        x, y, self._ra_at_xy_0, self._dec_at_xy_0, self._Mpix2a
    )