pygame window color not changing?

Question

pygame

Wanted to change the color of the pygame window, but the screen is always black. Please help me. Here is the code. (Where (pixel.screen_width, pixel.screen_height) they are both 900)

import sys
import pygame
from settings import Settings
def game():
 
# Экран.
    pygame.init()
pixel = Settings()
screen = pygame.display.set_mode((pixel.screen_width, pixel.screen_height))
pygame.display.set_caption("Play")
 
# Запуск цикла игры.
run = True
while run:
 
#Клавиатура и мышь.
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
 
# Отображение последнего прорисованного экрана.
screen.fill(pygame.Color(255, 0, 0))
pygame.display.flip()
 
game()