title: Sprite not adding to group to display on screen
body: <p>Traceback (most recent call last):
    File "***/Pcprojects/pygameKCC/kcc-shmup.py", line 49, in 
      all_sprites.update()</p>
  
  <h2>TypeError: unbound method update() must be called with Group instance as first argument (got nothing instead)</h2>
  
  <p>I'm following a tutorial that has working code (for him), and for my life I can't get this sprite to render. Can anyone tell me what I'm doing wrong? This is my first time with sprites other than a basic bouncy ball screen saver type thing. Thanks!</p>
  
  <pre><code>import pygame
  import random
  import sys
  import math
  
  #global constants
  WIDTH = 360
  HEIGHT = 480
  FPS = 30
  
  #define colors
  WHITE = (255, 255, 255)
  BLACK = (0, 0, 0)
  RED = (255, 0, 0)
  GREEN = (0, 255, 0)
  BLUE = (0, 0, 255)
  #YELLOW = (X, X, X)
  
  
  class Player(pygame.sprite.Sprite):
      #sprite for the player.
      def __init__(self):
          pygame.sprite.Sprite.__init__(self)
          #required image and collision rectangle
          self.image = pygame.Surface((50, 50))
          self.image.fill(GREEN)
          self.rect = self.image.get_rect()
          self.rect.center = (WIDTH / 2, HEIGHT / 2)
  
  #itialize pygame
  #itialize music mixer
  pygame.init()
  pygame.mixer.init()
  
  #create screen
  screen = pygame.display.set_mode((WIDTH, HEIGHT))
  pygame.display.set_caption("My Game")
  clock = pygame.time.Clock()
  
  #create a group for all sprites to belong to
  all_sprites = pygame.sprite.Group()
  player = Player()
  all_sprites.add(player)
  
  
  running = True
  while running:
  
      clock.tick(FPS)
  
      for event in pygame.event.get():
          if event.type == pygame.QUIT:
              running = False
  </code></pre>
  
  <p>#updated:</p>
  
  <pre><code>    all_sprites.update()
      screen.fill(BLACK)
      all_sprites.draw(screen)
      pygame.display.flip()
  
  pygame.quit()
  </code></pre>