Python - PyGame ayuda

import pygame, ctypes as ct

from pygame.locals import *

nRES = (572,323) ; lOK = True ; nPAUSA = 5

nNIVELY_0 = 290 ; nNIVELY_1 = 264 ; nNIVELY_2 = 238

nNIVELY_3 = 212 ; nNIVELY_4 = 186 ; nNIVELY_5 = 160

nNIVELY_6 = 134 ; nNIVELY_7 = 108 ; nNIVELY_8 = 82

nNIVELY_9 = 56

nNIVELX_0 = 35 ; nNIVELX_1 = 70 ; nNIVELX_2 = 107 ; nNIVELX_3 = 142

nNIVELX_4 = 179 ; nNIVELX_5 = 214 ; nNIVELX_6 = 251 ; nNIVELX_7 = 286

nNIVELX_8 = 323 ; nNIVELX_9 = 358 ; nNIVELX_10 = 395 ; nNIVELX_11 = 430

nNIVELX_12 = 467 ; nNIVELX_13 = 502

class eBarra(ct.Structure):

    _fields_=[('nX',ct.c_short),

    ('nY',ct.c_short),

    ('nD',ct.c_short),

    ('nI',ct.c_short),

    ('nT',ct.c_short)]

class eGarra(ct.Structure):

    _fields_=[('nX',ct.c_short),

    ('nY',ct.c_short),

    ('nD',ct.c_short),

    ('nI',ct.c_short)]

class eCarga(ct.Structure):

    _fields_=[('nX',ct.c_short),

    ('nY',ct.c_short),

    ('nD',ct.c_short),

    ('nI',ct.c_short)]

def Load_Image(sFile,transp = False):

    try: image = pygame.image.load(sFile)

    except pygame.error,message:

        raise SystemExit,message

    image = image.convert()

    if transp:

        color = image.get_at((0,0))

        image.set_colorkey(color,RLEACCEL)

    return image

def PyGame_Init():

    pygame.init()

    pygame.display.set_caption('Pregunta 5 proyecto 1')

    pygame.mouse.set_visible(True)

    return pygame.display.set_mode(nRES)

def Fig_Init():

    aImg = []

    aImg.append(Load_Image('Base.png',False))

    aImg.append(Load_Image('Barra.png',True))

    aImg.append(Load_Image('Carga.png',True))

    aImg.append(Load_Image('Garra.png',True))

    return aImg

def Pinta_Base():

    Panta.blit(aSprt[0],(0,0))

    return

def Pinta_Barra():

    Panta.blit(aSprt[1],(aBarra[0].nX,aBarra[0].nY))

    return

def Pinta_Carga():

    Panta.blit(aSprt[2],(111,268))

def Pinta_Garra():

    Panta.blit(aSprt[3],(108,277))

def Barra_Init():

    aBarra[0].nX = 7

    aBarra[0].nY = 280

    aBarra[0].nD = 0

    aBarra[0].nI = -1 # Sube

    aBarra[0].nT = nPAUSA

    return

def Pos_mouse():

    event = pygame.event.poll()

    if event.type == pygame.MOUSEBUTTONDOWN:

        return "(%d, %d)" % event.pos

Panta = PyGame_Init()

aSprt = Fig_Init()

aBarra = [ eBarra()]

aCarga = [ eCarga()]

aGarra = [ eGarra()]

Barra_Init()

while lOK:

    cKey = pygame.key.get_pressed()

    if cKey[pygame.K_ESCAPE]: lOK = False

    ev = pygame.event.get()

    for e in ev:

        if e.type == QUIT: lOK = False

    Pinta_Base()

    Pinta_Carga()

    Pinta_Barra()

    Pinta_Garra()

    pygame.display.flip()

    pygame.quit