[...] pygame.key.set_repeat(1,1) while running: for event in pygame.event.get(): keys = pygame.key.get_pressed() if keys[K_c]: [...] if keys[K_v]: [...] if keys[K_m]: [...] if keys[K_COMMA]: [...] [...] [...]
pygame incorrectly handles multiple keys pressed at a time. For example, take the example above and mess with the keys. What you'll notice is that when there is a group of keys pressed, when you release one of them, all remaining pressed keys will become in an unpressed state until another key is pressed. Using pygame 1.9.2, python 2.7.9 x86, known to occur on Linux and Windows.