python pygame update text label
<p>I wish to update a text label when I key press down but nothing happens. It probably have something to do with the loop but I am not sure how to fix it.</p>

<p>I am using pygame</p>

<pre><code>import pygame

pygame.init()

display_width = 800
display_height = 600

screen = pygame.display.set_mode((display_width, display_height))
done = False

pygame.display.set_caption('UTTER')

bg = pygame.image.load("wheel.bmp")

digitalFont = pygame.font.Font("digital-7.ttf",26)

mixValue = "03"

def updateLED (dial, value):
    if dial == "mix":
        mixLED = digitalFont.render(value, 1, (255,255,0))
        screen.blit(mixLED, (362, 166))


while not done:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

        elif event.type == pygame.KEYDOWN:
            if event.key == pygame.K_DOWN:
                updateLED("mix", "01")
                print("down")

    # Add this somewhere after the event pumping and before the display.flip()
    screen.blit(bg, (0, 0))

    updateLED ("mix", "03")

    pygame.display.update()

pygame.quit()
quit()
</code></pre>