code: def _err_param_train_data(train_data):
      return train_data
  
file_path: hyperparameter_hunter/tests/test_feature_engineering.py
imports: from hyperparameter_hunter.feature_engineering import merge_dfs, split_merged_df
  from hyperparameter_hunter.feature_engineering import DatasetNameReport, validate_dataset_names
  from hyperparameter_hunter.feature_engineering import get_engineering_step_params
  import pandas
  import pytest
label_desc: Use image node_id 7 for calling a global function with example usage: _err_param_train_data(train_data) and returns: train_data