old_contents: """
  Countdown to Liftoff!
  """
  
  # iterator variable
  count = 10
  
  # loop
  while count > 0:
      print(count)
      count -= 1
  
  print("Liftoff!")
  
new_contents: """
  Countdown to Liftoff!
  """
  
  # iterator variable
  count = 10
  
  # loop
  while count > 0:
      print(count)
      count -= 1 # count = count - 1
  
  print("Liftoff!")
  
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