import pygame
from pygame.locals import *
import sys

pygame.init()
display = pygame.display.set_mode((900, 900))
backround = pygame.Surface((50, 500))

Surface = pygame.Surface((30, 30))
Surface.fill((0,255,0))

pos = [175, 145]

while 1: 
    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_a:
                print("Key A has been pressed")
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_a:
                print("Key A has been released")  
                pos[0] += 50