如何在pygame中绘制一条在屏幕上移动的线

import pygame
import sys

pygame.init()
screen = pygame.display.set_mode((800, 600))

start_pos = (100, 100)
end_pos = (700, 500)

line_color = (255, 0, 0)  # 红色
line_width = 3

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()

    # 清空屏幕
    screen.fill((255, 255, 255))

    # 绘制线
    pygame.draw.line(screen, line_color, start_pos, end_pos, line_width)

    # 更新屏幕显示
    pygame.display.flip()