import pygame, sys, random

def draw_floor():

    screen.blit(floor,(floor_x_pos,650))

    screen.blit(floor,(floor_x_pos + 432,650))

def create_pipe():

    random_pipe_pos = random.choice(pipe_height)

    bottom_pipe = pipe_surface.get_rect(midtop=(500,random_pipe_pos))

    top_pipe = pipe_surface.get_rect(midtop=(500,random_pipe_pos-650))

    return bottom_pipe , top_pipe

def move_pipe(pipes):

    for pipe in pipes:

        pipe.centerx -= 5

    return pipes

def draw_pipe(pipes):

    for pipe in pipes:

        if pipe.bottom >= 768 :

            screen.blit(pipe_surface,pipe)

        else:

            flip_pipe = pygame.transform.flip(pipe_surface,False,True)

pygame.init()

screen = pygame.display.set_mode((432,768))

clock = pygame.time.Clock()

gravity = 0.25

bird_movement = 0

bg = pygame.image.load('assets/background-night.png').convert()

bg = pygame.transform.scale2x(bg)

floor = pygame.image.load('assets/floor.png').convert()

floor = pygame.transform.scale2x(floor)

floor_x_pos = 0

bird = pygame.image.load('assets/yellowbird-midflap.png').convert()

bird = pygame.transform.scale2x(bird)

bird_rect = bird.get_rect(center = (100,384))

pipe_surface = pygame.image.load('assets/pipe-green.png').convert()

pipe_surface = pygame.transform.scale2x(pipe_surface)

pipe_list = []

spawnpipe = pygame.USEREVENT

pygame.time.set_timer(spawnpipe , 1200)

pipe_height = [200,300,400]

while True:

    for event in pygame.event.get():

        if event.type == pygame.QUIT:

            pygame.quit()

            sys.exit()

        if event.type == pygame.KEYDOWN:

            if event.key == pygame.K_UP or event.key == pygame.K_SPACE:

                bird_movement = 0

                bird_movement = -11.

            if event.type == spawnpipe:

                pipe_list.extend(create_pipe())        

    screen.blit(bg,(0,0))

    bird_movement += gravity

    bird_rect.centery += bird_movement

    screen.blit(bird,bird_rect)

    pipe_list = move_pipe(pipe_list)

    draw_pipe(pipe_list)

    floor_x_pos -= 1

    draw_floor()

    if floor_x_pos <= -432 :

        floor_x_pos = 0

    pygame.display.update()

    clock.tick(120)

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