Building a screen saver

We will start by building a screen saver. The program will consist of several random-colored and random-sized balls bouncing all over the screen at random velocity, as shown in the following screenshot:

Let's create a class to generate balls with random attributes. Accordingly, we define a new class named RandomBall. Refer the code file 8.01_screensaver:

class RandomBall:

def __init__(self, canvas):
 self.canvas = canvas
 self.screen_width = canvas.winfo_screenwidth()
 self.screen_height = canvas.winfo_screenheight()
 self.create_ball()

def create_ball(self):
 self.generate_random_attributes()
 self.create_oval() 

def generate_random_attributes(self):
 self.radius = r = randint(40, 70)
 self.x_coordinate = randint(r, self.screen_width - r)
 self.y_coordinate = randint(r, self.screen_height - r)
 self.x_velocity = randint(6, 12)
 self.y_velocity = randint(6, 12)
 self.color = self.generate_random_color()

def generate_random_color(self):
 r = lambda: randint(0, 0xffff...