How do I change the color of ellipse to a randint every two seconds in Kivy, using random integers

class CanvasExample5(Widget):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self.ball_size = dp(50)
        with self.canvas:
            self.color = Color(0, 1, 0)
            self.ball = Ellipse(pos=self.center, size=(self.ball_size, self.ball_size))
        Clock.schedule_interval(self.update, 1/60)
        Clock.schedule_interval(self.colour, 1)
        self.vx = dp(5)
        self.vy = dp(3)

    def on_size(self, *args):
        self.ball.pos = (self.center_x-self.ball_size/2, self.center_y-self.ball_size/2)

    def colour(self, *args):
        random_1 = random.randint(0, 255)
        random_2 = random.randint(0, 255)
        random_3 = random.randint(0, 255)
        self.color = Color(random_1, random_2, random_3)

The Ellipse graphics command uses the Color that is in effect at the time it is executed, so changing the Color afterwards will have no effect on the Ellipse. One fix is to clear the canvas and redraw the Ellipse with the new Color:

def colour(self, *args):
    random_1 = random.random()
    random_2 = random.random()
    random_3 = random.random()
    self.canvas.clear()
    with self.canvas:
        Color(random_1, random_2, random_3)
        self.ball = Ellipse(pos=self.center, size=(self.ball_size, self.ball_size))

Also, note that the Color command takes values between 0 and 1, not 0 to 255.