code: def pyunit_as_data_frame():
      smallbike = h2o.import_file(
          pyunit_utils.locate("smalldata/jira/citibike_head.csv")
      )
  
      ##use_pandas = False
      small_bike_list = smallbike.as_data_frame(use_pandas=False)
      assert isinstance(small_bike_list, list)
      assert len(small_bike_list[0]) == smallbike.ncol
      assert (
          len(small_bike_list) == smallbike.nrow + 1
      )  # one extra for header
  
      smallbike_noheader = smallbike.as_data_frame(
          use_pandas=False, header=False
      )
      assert len(smallbike_noheader) == smallbike.nrow
  
      head_small_bike = smallbike.head(rows=5, cols=2)
      tail_small_bike = smallbike.tail(rows=5, cols=2)
      assert len(head_small_bike[0]) == len(tail_small_bike[0]) == 5
      assert len(head_small_bike) == len(tail_small_bike) == 5
      # assert head_small_bike[1][-1] == tail_small_bike[1][1]  # TODO
  
      ##use_pandas = True
      small_bike_pandas = smallbike.as_data_frame(use_pandas=True)
      assert small_bike_pandas.__class__.__name__ == "DataFrame"
      assert small_bike_pandas.shape == (smallbike.nrow, smallbike.ncol)
  
      head_small_bike_pandas = smallbike.head(rows=5).as_data_frame(
          True
      )
      tail_small_bike_pandas = smallbike.tail(rows=5).as_data_frame(
          True
      )
      assert (
          head_small_bike_pandas.shape
          == tail_small_bike_pandas.shape
          == (5, smallbike.ncol)
      )
      assert (
          head_small_bike_pandas.loc[1][2]
          == small_bike_pandas.loc[1][2]
      )
      assert (
          tail_small_bike_pandas.loc[2][3]
          == small_bike_pandas.loc[6][3]
      )
      assert (
          head_small_bike_pandas.loc[4][0]
          == tail_small_bike_pandas.loc[0][0]
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: pyunit_as_data_frame() without return types