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# import the pygame module
import pygame

# import random for random numbers!
import random

# import pygame.locals for easier access to key coordinates
from pygame.locals import *


class Player(pygame.sprite.Sprite):
    def __init__(self):
        super(Player, self).__init__()
        self.surf = pygame.Surface((75, 25))
        self.surf.fill((255, 255, 255))
        self.rect = self.surf.get_rect()

    def update(self, pressed_keys):
        if pressed_keys[K_UP]:
            self.rect.move_ip(0, -5)
        if pressed_keys[K_DOWN]:
            self.rect.move_ip(0, 5)
        if pressed_keys[K_LEFT]:
            self.rect.move_ip(-5, 0)
        if pressed_keys[K_RIGHT]:
            self.rect.move_ip(5, 0)

        # Keep player on the screen
        if self.rect.left < 0:
            self.rect.left = 0
        elif self.rect.right > 800:
            self.rect.right = 800
        if self.rect.top <= 0:
            self.rect.top = 0
        elif self.rect.bottom >= 600:
            self.rect.bottom = 600


class Enemy(pygame.sprite.Sprite):
    def __init__(self):
        super(Enemy, self).__init__()
        self.surf = pygame.Surface((20, 10))
        self.surf.fill((255,255,255))
        self.rect = self.surf.get_rect(
            center=(random.randint(820, 900), random.randint(0, 600))
        )
        self.speed = random.randint(5, 20)

    def update(self):
        self.rect.move_ip(-self.speed, 0)
        if self.rect.right < 0:
            self.kill()


# initialize pygame
pygame.init()

# create the screen object
# here we pass it a size of 800x600
screen = pygame.display.set_mode((800, 600))

# Create a custom event for adding a new enemy.
ADDENEMY = pygame.USEREVENT + 1
pygame.time.set_timer(ADDENEMY, 250)

# create our 'player'; right now he's just a rectangle
player = Player()

background = pygame.Surface(screen.get_size())
background.fill((0, 0, 0))

enemies = pygame.sprite.Group()
all_sprites = pygame.sprite.Group()
all_sprites.add(player)

running = True

while running:
    for event in pygame.event.get():
        if event.type == KEYDOWN:
            if event.key == K_ESCAPE:
                running = False
        elif event.type == QUIT:
            running = False
        elif(event.type == ADDENEMY):
            new_enemy = Enemy()
            enemies.add(new_enemy)
            all_sprites.add(new_enemy)
    screen.blit(background, (0, 0))
    pressed_keys = pygame.key.get_pressed()
    player.update(pressed_keys)
    enemies.update()
    for entity in all_sprites:
        screen.blit(entity.surf, entity.rect)

    if pygame.sprite.spritecollideany(player, enemies):
        player.kill()

    pygame.display.flip()


    

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