如何用PyGame实现键值录入？

import pygame

pygame.init()

window_width = 800
window_height = 600
window = pygame.display.set_mode((window_width, window_height))
pygame.display.set_caption("键值录入")

font = pygame.font.Font(None, 36)

text = font.render("按下的键值：", True, (255, 255, 255))
text_rect = text.get_rect()
text_rect.center = (window_width // 2, window_height // 2)

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN:
            key_name = pygame.key.name(event.key)
            text = font.render("按下的键值：" + key_name, True, (255, 255, 255))

    window.fill((0, 0, 0))
    window.blit(text, text_rect)
    pygame.display.flip()

pygame.quit()