class_docstr: TimeSequence feature engineering
code: def _get_optional_parameters(self):
      return {"past_seq_len", "selected_features"}
  
imports: from bigdl.chronos.autots.deprecated.feature.utils import save_config
  from bigdl.chronos.autots.deprecated.feature.abstract import BaseFeatureTransformer
  from bigdl.chronos.utils import deprecated
  import sklearn
  from sklearn.preprocessing import StandardScaler
  import pandas
  import numpy
  import json
  from packaging import version
label_desc: Use image node_id 26 for calling the TimeSequenceFeatureTransformer obj's underlying member method code with example usage: obj._get_optional_parameters() and returns: unknown