def show_rects_approaching_area(self):
    for new_rects in self.rect_list:
        self.transform_between_riemann_rects(self.rects, new_rects)
def show_rects_approaching_area(self):
    for new_rects in self.rect_list:
        self.transform_between_riemann_rects(self.rects, new_rects)