size = [400, 400] screen = pygame.display.set_mode(size) clock = pygame.time.Clock() while True: for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit() sys.exit() # check if key is pressed # if you use event.key here it will give you error at runtime if event.type == pygame.KEYUP: if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT \ or event.key == pygame.K_UP: conn.sendMessage("stop\n") continue if event.type == pygame.KEYDOWN: if event.key == pygame.K_LEFT: conn.sendMessage("turnleft\n") if event.key == pygame.K_RIGHT: conn.sendMessage("turnright\n") if event.key == pygame.K_l: conn.sendMessage("left 300\n") if event.key == pygame.K_r: conn.sendMessage("right 300\n") if event.key == pygame.K_UP: conn.sendMessage("up\n") if event.key == pygame.K_a: conn.sendMessage("measure\n") if event.key == pygame.K_q: