old_contents: 
  if random:
      numbers = 1
  else:
      numbers = 1, 2, 3
  
  if isinstance(numbers, list):
      for n in numbers:
          print(n)
  else:
      for n in numbers:
          print(n)
  
new_contents: 
  if random:
      numbers = 1
  else:
      numbers = 1, 2, 3
  
  if isinstance(numbers, tuple):
      for n in numbers:
          print(n)
  else:
      for n in numbers:
          print(n)
  
subject: Fix example 3