code: def pyunit_unique():
      iris = h2o.import_file(
          pyunit_utils.locate("smalldata/iris/iris.csv")
      )
      uniques = iris[4].unique()
      rows, cols = uniques.dim
      assert (
          rows == 3 and cols == 1
      ), "Expected 3 rows and 1 column, but got {0} rows and {1} column".format(
          rows, cols
      )
      assert (
          "Iris-setosa" in uniques[0]
      ), "Expected Iris-setosa to be in the set of unique species, but it wasn't"
      assert (
          "Iris-virginica" in uniques[0]
      ), "Expected Iris-virginica to be in the set of unique species, but it wasn't"
      assert (
          "Iris-versicolor" in uniques[0]
      ), "Expected Iris-versicolor to be in the set of unique species, but it wasn't"
  
      fr = h2o.create_frame(rows=5, cols=1, time_fraction=1)
      assert fr.type(0) == "time"
      uf = fr.unique()
      assert uf.type(0) == "time"
      uf.refresh()
      assert uf.type(0) == "time"
  
      prostate = h2o.import_file(
          pyunit_utils.locate(
              "smalldata/parser/csv2orc/prostate_NA.csv"
          )
      )
      prostate["GLEASON"] = prostate["GLEASON"].asfactor()
      uniques = prostate["GLEASON"].unique(include_nas=True)
      uniques_without_nas = prostate["GLEASON"].unique()
      prostate_pandas = prostate.as_data_frame()
      uniques_pandas = prostate_pandas["GLEASON"].unique()
      assert uniques.nrows == len(uniques_pandas)
      assert uniques_without_nas.nrows == len(uniques_pandas) - 1
  
      # make sure domains are recalculated with each temp assign
      df_example = h2o.H2OFrame(
          {
              "time": ["M", "M", "M", "D", "D", "M", "M", "D"],
              "amount": [1, 4, 5, 0, 0, 1, 3, 0],
          }
      )
  
      df_example["amount"] = df_example["amount"].asfactor()
      filtered = df_example[df_example["time"] == "D", "amount"]
      uniques = filtered["amount"].unique()
      assert len(uniques) == 1
      assert uniques.as_data_frame().iat[0, 0] == 0
  
label_desc: Use image node_id 1 for calling a global function with example usage: pyunit_unique() without return types