Simple OXO

import pygame
pygame.init()
pygame.display.set_caption('Drawing')
window = pygame.display.set_mode((600, 600))
running = True
pygame.draw.rect(window, (0, 255, 0),(0, 200, 600, 10))
pygame.draw.rect(window, (0, 255, 0),(0, 400, 600, 10))
pygame.draw.rect(window, (0, 255, 0),(200, 0, 10, 600))
pygame.draw.rect(window, (0, 255, 0),(400, 0, 10, 600))
while running:
    for event in pygame.event.get():
        (mouseX, mouseY) = pygame.mouse.get_pos()
        (pressed1,pressed2,pressed3) = pygame.mouse.get_pressed()
        if pressed1 == 1:
            pygame.draw.rect(window, (0, 0, 255),(mouseX, mouseY, 5, 5))
        pygame.display.update()
        if event.type == pygame.QUIT:
            running = False