old_contents: import pyglet
  import resource
  
  class Bird(pyglet.sprite.Sprite):
      GRAVITY_ACC = 500
      ANGULAR_ACC = 350
  
      def __init__(self, *args, **kwargs):
          super(Bird, self).__init__(*args, **kwargs)
          self.speed = 0
          self.ang_speed = 0
          self.jumped = False
  
      def update(self, dt):
          from game import Game
          # bird only moves up and down, so the speed is the y speed
          self.speed += Bird.GRAVITY_ACC * dt
          self.ang_speed += Bird.ANGULAR_ACC * dt
          if self.jumped:
              self.speed = -200
              self.ang_speed = -400
          self.y -= self.speed * dt
          self.rotation += self.ang_speed * Game.TIME_INTERVAL
          if self.y > Game.WINDOW_HEIGHT:
              self.y = Game.WINDOW_HEIGHT
              self.speed = 0
              if Game.sound:
                  resource.tap_sound.play()
          if self.rotation < -20:
              self.rotation = -20
              self.ang_speed = 0
          if self.rotation > 90:
              self.rotation = 90
          self.jumped = False
  
      def rotate(self, dt):
          self.rotation += self.ang_speed * dt
  
      # tapping the screen, the bird will jump up
      def jump(self):
          self.jumped = True
  
  
          
  
  
new_contents: import pyglet
  import resource
  
  class Bird(pyglet.sprite.Sprite):
      GRAVITY_ACC = 500
      ANGULAR_ACC = 350
  
      def __init__(self, *args, **kwargs):
          super(Bird, self).__init__(*args, **kwargs)
          self.speed = 0
          self.ang_speed = 0
          self.jumped = False
  
      def update(self, dt):
          from game import Game
          # bird only moves up and down, so the speed is the y speed
          self.speed += Bird.GRAVITY_ACC * dt
          self.ang_speed += Bird.ANGULAR_ACC * dt
          if self.jumped:
              self.speed = -200
              self.ang_speed = -400
              if Game.sound:
                  resource.tap_sound.play()
          self.y -= self.speed * dt
          self.rotation += self.ang_speed * Game.TIME_INTERVAL
          if self.y > Game.WINDOW_HEIGHT:
              self.y = Game.WINDOW_HEIGHT
              self.speed = 0
          if self.rotation < -20:
              self.rotation = -20
              self.ang_speed = 0
          if self.rotation > 90:
              self.rotation = 90
          self.jumped = False
  
      def rotate(self, dt):
          self.rotation += self.ang_speed * dt
  
      # tapping the screen, the bird will jump up
      def jump(self):
          self.jumped = True
  
  
          
  
  
subject: fix bug