code: def levels_nlevels_setlevel_setLevels_test():
      iris = h2o.import_file(
          path=pyunit_utils.locate("smalldata/iris/iris.csv")
      )
  
      # frame (default)
      levels = iris.levels()
      nlevels = iris.nlevels()
  
      # frame (w/ index)
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert {
          "Iris-setosa",
          "Iris-versicolor",
          "Iris-virginica",
      } == set(levels), "Expected levels to be {0}, but got {1}".format(
          {"Iris-setosa", "Iris-versicolor", "Iris-virginica"}, levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
  
      # vec
      iris[4] = iris[4].set_level(level="Iris-setosa")
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert {
          "Iris-setosa",
          "Iris-versicolor",
          "Iris-virginica",
      } == set(levels), "Expected levels to be {0}, but got {1}".format(
          {"Iris-setosa", "Iris-versicolor", "Iris-virginica"}, levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
      assert iris[0, 4] == "Iris-setosa"
  
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert {
          "Iris-setosa",
          "Iris-versicolor",
          "Iris-virginica",
      } == set(levels), "Expected levels to be {0}, but got {1}".format(
          {"Iris-setosa", "Iris-versicolor", "Iris-virginica"}, levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
  
      iris[4] = iris[4].set_level(level="Iris-versicolor")
      levels = iris[4].levels()[0]
      nlevels = iris.nlevels()[4]
      assert {
          "Iris-setosa",
          "Iris-versicolor",
          "Iris-virginica",
      } == set(levels), "Expected levels to be {0}, but got {1}".format(
          set(["Iris-setosa", "Iris-versicolor", "Iris-virginica"]),
          levels,
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
      assert iris[0, 4] == "Iris-versicolor"
  
      levels = iris[1].levels()
      nlevels = iris[1].nlevels()
      assert (
          levels == []
      ), "Expected levels to be [], but got {0}".format(levels)
      assert (
          nlevels == 0
      ), "Expected nlevels to be 0, but got {0}".format(nlevels)
  
      ################### reimport, set new domains, rerun tests ###################################
      iris = h2o.import_file(
          path=pyunit_utils.locate("smalldata/iris/iris.csv")
      )
      iris[4] = iris[4].set_levels(levels=["a", "b", "c"])
  
      # frame (default)
      levels = iris.levels()
      nlevels = iris.nlevels()
  
      # frame (w/ index)
      levels = iris[4].levels()[0]
      nlevels = iris.nlevels()[4]
      assert set(["a", "b", "c"]) == set(
          levels
      ), "Expected levels to be {0}, but got {1}".format(
          set(["a", "b", "c"]), levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
  
      # vec
      iris[4] = iris[4].set_level(level="a")
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert set(["a", "b", "c"]) == set(
          levels
      ), "Expected levels to be {0}, but got {1}".format(
          set(["a", "b", "c"]), levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
      assert iris[0, 4] == "a"
  
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert set(["a", "b", "c"]) == set(
          levels
      ), "Expected levels to be {0}, but got {1}".format(
          set(["a", "b", "c"]), levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
  
      iris[4] = iris[4].set_level(level="b")
      levels = iris[4].levels()[0]
      nlevels = iris[4].nlevels()[0]
      assert set(["a", "b", "c"]) == set(
          levels
      ), "Expected levels to be {0}, but got {1}".format(
          set(["a", "b", "c"]), levels
      )
      assert (
          nlevels == 3
      ), "Expected nlevels to be 3, but got {0}".format(nlevels)
      assert iris[0, 4] == "b"
  
      levels = iris[1].levels()
      nlevels = iris[1].nlevels()
      assert (
          levels == []
      ), "Expected levels to be [], but got {0}".format(levels)
      assert (
          nlevels == 0
      ), "Expected nlevels to be 0, but got {0}".format(nlevels)
  
      one_column_frame = iris[4]
      one_column_frame = one_column_frame.set_level(level="c")
      assert one_column_frame[0, 0] == "c"
  
label_desc: Use image node_id 1 for calling a global function with example usage: levels_nlevels_setlevel_setLevels_test() without return types