pygame time animation

[lewashby]

background_image_filename = 'sushiplate.jpg'
sprice_image_filename = 'fugu.png'

import pygame
from pygame.locals import *
from sys import exit

pygame.init()

screen = pygame.display.set_mode((640, 480), 0, 32)

background = pygame.image.load(background_image_filename).convert()
sprite = pygame.image.load(sprice_image_filename)

# our clock object
clock = pygame.time.Clock()

x1 = 0.
x2 = 0.

# speed in pixels per second
speed = 250.

frame_no = 0

while True:
    
    for event in pygame.event.get():
        if event.type == QUIT:
            exit()
            
    screen.blit(background, (0, 0))
    screen.blit(sprite, (x1, 50))
    screen.blit(sprite, (x2, 250))
    
    time_passed = clock.tick(30)
    time_passed_seconds = time_passed / 1000.0
    
    distance_moved = time_passed_seconds * speed
    x1 += distance_moved
    
    if (frame_no % 5) == 0:
        distance_moved = time_passed_seconds * speed
        x2 += distance_moved * 5
        
    # if the image goes of the end of the screen, move it back
    if x1 > 640.:
        x1 -= 640.
    if x2 > 640.:
        x2 -= 640.
        
    pygame.display.update()
    frame_no += 1

Could someone please explain to me what going on in the if statement. I don't understand why there is a duplicate line of code in the if statement that was also just a few lines back. The variable frame_no is also getting me. It's already 0 so the remainder of 0 \ 5 is always going to be 0. Thanks for any and all replies.

[Beat_Slayer]

The if statements are no repeated, theres one if for each sprite.

The if of line 42 moves the second sprite (x2) every 5 frames, or being said every 5 movements of the first sprite (x1)

The frame counter is incremented on line 52.

Cheers and Happy coding