class_docstr: Defines and formats data for the Alpha158 dataset.
  
  Attributes:
    column_definition: Defines input and data type of column used in the
      experiment.
    identifiers: Entity identifiers used in experiments.
docstr: Returns default optimised model parameters.
code: def get_default_model_params(self):
      """Returns default optimised model parameters."""
  
      model_params = {
          "dropout_rate": 0.4,
          "hidden_layer_size": 160,
          "learning_rate": 0.0001,
          "minibatch_size": 128,
          "max_gradient_norm": 0.0135,
          "num_heads": 1,
          "stack_size": 1,
      }
  
      return model_params
  
file_path: qlib/examples/benchmarks/TFT/data_formatters/qlib_Alpha158.py
imports: import data_formatters.base
  import libs.utils
  import sklearn.preprocessing
label_desc: Use image node_id 7 for calling the Alpha158Formatter obj's underlying member method code with example usage: obj.get_default_model_params() and returns: model_params