Push
  Variable Natural : Type.
  Alias ℕℕ : Natural.
  Variable x : Natural.
  print Environment 1.
  SetOption pp::unicode false.
  print Environment 1.
  SetOption pp::unicode true.
  print Environment 1.
  Alias NN : Natural.
  print Environment 2.
  Alias ℕℕℕ : Natural.
  print Environment 3.
  SetOption pp::unicode false.
  print Environment 3.
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