old_contents: d = dict.fromkeys([1, 2, 3, 4])
  l = list(d.keys())
  l.sort()
  print(l)
  
  d = dict.fromkeys([1, 2, 3, 4], 42)
  l = list(d.values())
  l.sort()
  print(l)
  
  
new_contents: d = dict.fromkeys([1, 2, 3, 4])
  l = list(d.keys())
  l.sort()
  print(l)
  
  d = dict.fromkeys([1, 2, 3, 4], 42)
  l = list(d.values())
  l.sort()
  print(l)
  
  # argument to fromkeys is a generator
  d = dict.fromkeys(i + 1 for i in range(1))
  print(d)
  
subject: Add test for dict.fromkeys where arg is a generator.