pygame sprite animation loop not working properly

Question

so just a bit a go I was asking for help with passing a list as into a sprite Class and you guys helped out but I ran into another wall. the problem comes when I try to loop the sprite list.

Here is the sprite class:

    class Player(pygame.sprite.Sprite):
    def __init__ (self,frames,*groups):
        self.frame = 0
        super(Player,self).__init__(*groups)

        self.images = []
        self.images.append(frames[self.frame])
        self.image = self.images[self.frame]
        self.rect = pygame.rect.Rect((320,240),self.image.get_size())

    def update(self):

        key = pygame.key.get_pressed()
        if key[pygame.K_LEFT]:
            self.rect.x -= 10
            self.frame += 10
        if key[pygame.K_RIGHT]:
            self.rect.x += 10
            self.frame += 1
        if key[pygame.K_UP]:
            self.rect.y -= 10
            self.frame += 1 
        if key[pygame.K_DOWN]:
            self.rect.y += 10
            self.frame += 1 
        if self.frame > 3:
            self.frame = 0 

and here is the main game loop:

class Game(object):
    def main(self, screen): 
        sprite = pygame.image.load('test.png')
        frames =  sprite_system().slice_sheet(sprite,0,0,64,64,4)
        sprites = pygame.sprite.Group()
        self.player = Player(frames,sprites)
        clock = pygame.time.Clock()
        while 1:
            clock.tick(30)
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    return
                if event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
                    return

            screen.fill((200, 200, 200))
            sprites.update()
            sprites.draw(screen)
            pygame.display.flip()
            pygame.sprite.Group.sprites

if __name__ == '__main__':
    pygame.init()
    screen = pygame.display.set_mode((640, 480))
    Game().main(screen)         

the problem i think comes in when i set up the self.frame it sets it as 0 every time something is called but i just cant see what it is maybe you guys can help

self.frame is set to 0 here self.frame = 0 super(Player,self).init(*groups)

        self.images = []
        self.images.append(frames[self.frame])
        self.image = self.images[self.frame]
        self.rect = pygame.rect.Rect((320,240),self.image.get_size())

and is needed also here to loop through the animation:

def update(self):

        key = pygame.key.get_pressed()
        if key[pygame.K_LEFT]:
            self.rect.x -= 10
            self.frame += 10
        if key[pygame.K_RIGHT]:
            self.rect.x += 10
            self.frame += 1
        if key[pygame.K_UP]:
            self.rect.y -= 10
            self.frame += 1 
        if key[pygame.K_DOWN]:
            self.rect.y += 10
            self.frame += 1 
        if self.frame > 3:
            self.frame = 0 

Edit :

the sprite sytem class

class sprite_system(object):
    def slice_sheet(self,sprite_sheet,sprite_start_x,sprite_start_y,sprite_size_x,sprite_size_y,sheet_frames):
        frame = []
        sheet_start = 1 
        frame_pos = 0
        sprite_start_x_base = sprite_size_x
        while sheet_start <= sheet_frames:
            sheet = sprite_sheet
            sheet.set_clip(pygame.Rect(sprite_start_x,sprite_start_y,sprite_size_x,sprite_size_y))
            sprite_clip = sheet.subsurface(sheet.get_clip())
            frame.append(sprite_clip)
            sprite_start_x += sprite_start_x_base
            sheet_start += 1
        return frame

Answer 1

• You're not placing the sprites in the sprite.Group
• Where is sprite_system().slice_sheet()?

• This line does nothing

      pygame.sprite.Group.sprites