code: def test_autoformer_forecaster_fit_val_tsdataset(self):
      train, val, test = create_tsdataset(val_ratio=0.1)
      forecaster = AutoformerForecaster(
          past_seq_len=24,
          future_seq_len=5,
          input_feature_num=2,
          output_feature_num=2,
          label_len=12,
          freq="s",
          seed=0,
      )
      forecaster.fit(train, val, epochs=3, batch_size=32)
      forecaster.predict(test)
  
imports: import numpy
  import pandas
  import tempfile
  import os
  from bigdl.chronos.utils import LazyImport
  from bigdl.chronos.data import TSDataset
  from unittest import TestCase
  import pytest
  from ..None import op_torch, op_automl
label_desc: Use image node_id 22 for calling the TestChronosModelAutoformerForecaster obj's underlying member method code with example usage: obj.test_autoformer_forecaster_fit_val_tsdataset() without return types