Fill in the missing blocks of code below the comments in the file, which should create a mini game with soccer balls hitting blocks.

import pygame

from pygame.locals import *

pygame.init()

class Ball(pygame.sprite.Sprite):

def __init__(self):

pygame.sprite.Sprite.__init__(self) #construct the parent component

self.image = pygame.image.load("small_ball.png").convert_alpha()

self.rect = self.image.get_rect() #loads the rect from the image

#set the position, direction, and speed of the ball

self.rect.left = random.randrange(0,screen.get_width()-self.rect.width)

self.rect.top = random.randrange(0,screen.get_height()-self.rect.height)

self.dir_x = random.choice([-1,1])

self.dir_y = random.choice([-1,1])

self.speed = random.randrange(1,4)

def update(self):

#Handle the walls by changing direction(s)

if self.rect.left < 0 or self.rect.right >= screen.get_width():

self.dir_x *= -1

if self.rect.top < 0 or self.rect.bottom >= screen.get_height():

self.dir_y *= -1

self.rect.move_ip(self.speed*self.dir_x, self.speed*self.dir_y)

class Block(pygame.sprite.Sprite):

def __init__(self, colour):

pygame.sprite.Sprite.__init__(self)

self.image = pygame.Surface((10,10)).convert()

self.image.fill(colour)

self.rect = self.image.get_rect()

#set the position of the block

self.rect.left = random.randrange(0,screen.get_width()-self.rect.width)

self.rect.top = random.randrange(0,screen.get_height()-self.rect.height)

#Start of game

screen = pygame.display.set_mode((640, 480))

#make 8 balls and put them in a group called ball_group

#make 1000 blocks in random colours and a separate group for them called block_group

background = pygame.Surface(screen.get_size()).convert()

background.fill((255, 255, 255))

screen.blit(background, (0,0))

clock = pygame.time.Clock()

keep_going = True

while keep_going:

clock.tick(30)

for ev in pygame.event.get():

if ev.type == QUIT:

keep_going = False

#for every ball in the group, check for collisions, killing the blocks hit

#stop the loop when all the blocks are gone

#Update the screen

ball_group.clear(screen, background)

block_group.clear(screen, background)

ball_group.update()

block_group.draw(screen)

ball_group.draw(screen)