text: def test_Dict():
      x: dict[i32, i32]
      x = {1: 2, 3: 4}
      # x = {1: "2", "3": 4} -> sematic error
  
      y: dict[str, i32]
      y = {"a": -1, "b": -2}
  
      z: i32
      z = y["a"]
      z = y["b"]
      z = x[1]
  