code: def test_look_back_value(self):
      target_col = "values"
      future_seq_len = np.random.randint(2, 6)
      train_df, test_df, tsp, test_sample_num = self.get_input_tsp(
          future_seq_len, target_col
      )
      # test min_past_seq_len < 2
      tsp.fit(train_df, test_df, recipe=RandomRecipe(look_back=(1, 2)))
      # test max_past_seq_len < 2
      with pytest.raises(ValueError, match=r".*max look back value*."):
          tsp.fit(
              train_df, test_df, recipe=RandomRecipe(look_back=(0, 1))
          )
      # test look_back value < 2
      with pytest.raises(
          ValueError,
          match=r".*look back value should not be smaller than 2*.",
      ):
          tsp.fit(train_df, test_df, recipe=RandomRecipe(look_back=1))
  
      # test look back is None
      with pytest.raises(
          ValueError, match=r".*look_back should be either*."
      ):
          tsp.fit(
              train_df, test_df, recipe=RandomRecipe(look_back=None)
          )
      # test look back is str
      with pytest.raises(
          ValueError, match=r".*look_back should be either*."
      ):
          tsp.fit(train_df, test_df, recipe=RandomRecipe(look_back="a"))
      # test look back is float
      with pytest.raises(
          ValueError, match=r".*look_back should be either*."
      ):
          tsp.fit(train_df, test_df, recipe=RandomRecipe(look_back=2.5))
      # test look back range is float
      with pytest.raises(
          ValueError, match=r".*look_back should be either*."
      ):
          tsp.fit(
              train_df, test_df, recipe=RandomRecipe(look_back=(2.5, 3))
          )
  
imports: import shutil
  import tempfile
  import pytest
  from test.zoo.pipeline.utils.test_utils import ZooTestCase
  from zoo.chronos.autots.deprecated.pipeline.time_sequence import load_ts_pipeline
  from zoo.chronos.autots.deprecated.regression.time_sequence_predictor import TimeSequencePredictor
  from zoo.chronos.autots.deprecated.feature.time_sequence import TimeSequenceFeatureTransformer
  from zoo.chronos.autots.deprecated.model.time_sequence import TimeSequenceModel
  from zoo.orca.automl.metrics import Evaluator
  from zoo.chronos.autots.deprecated.config.recipe import *
  import numpy
  import pandas
  from numpy.testing import assert_array_almost_equal
  import os
label_desc: Use image node_id 6 for calling the TestTimeSequencePipeline obj's underlying member method code with example usage: obj.test_look_back_value() without return types