def get_four_corners_from_2_corners(x1, y1, x2, y2):
    """
    Function returns all corners of a bounding box given 2 corners

    Args:
        x1, y1, x3, y2 (int) - top left and bottom right corners of
            box
        returns
            list containing all corners of box. 
    """
    return [x1, y1, x1, y2, x2, y2, x2, y1]