code: def test_python_errors(rating_true, rating_pred):
      with pytest.raises(ColumnMismatchError):
          rmse(rating_true, rating_true, col_user="not_user")
  
      with pytest.raises(ColumnMismatchError):
          mae(
              rating_pred,
              rating_pred,
              col_rating=DEFAULT_PREDICTION_COL,
              col_user="not_user",
          )
  
      with pytest.raises(ColumnMismatchError):
          rsquared(rating_true, rating_pred, col_item="not_item")
  
      with pytest.raises(ColumnMismatchError):
          exp_var(
              rating_pred,
              rating_pred,
              col_rating=DEFAULT_PREDICTION_COL,
              col_item="not_item",
          )
  
      with pytest.raises(ColumnMismatchError):
          precision_at_k(
              rating_true, rating_pred, col_prediction="not_prediction"
          )
  
      with pytest.raises(ColumnMismatchError):
          recall_at_k(
              rating_true, rating_pred, col_prediction="not_prediction"
          )
  
      with pytest.raises(ColumnMismatchError):
          ndcg_at_k(rating_true, rating_true, col_user="not_user")
  
      with pytest.raises(ColumnMismatchError):
          map_at_k(
              rating_pred,
              rating_pred,
              col_rating=DEFAULT_PREDICTION_COL,
              col_user="not_user",
          )
  
imports: import numpy
  import pandas
  import pytest
  from unittest.mock import Mock
  from sklearn.preprocessing import minmax_scale
  from pandas.testing import assert_frame_equal
  from recommenders.utils.constants import DEFAULT_USER_COL, DEFAULT_ITEM_COL, DEFAULT_RATING_COL, DEFAULT_PREDICTION_COL
  from recommenders.evaluation.python_evaluation import _check_column_dtypes, merge_rating_true_pred, merge_ranking_true_pred, rmse, mae, rsquared, exp_var, get_top_k_items, precision_at_k, recall_at_k, ndcg_at_k, map_at_k, map, auc, logloss, user_diversity, diversity, historical_item_novelty, novelty, user_item_serendipity, user_serendipity, serendipity, catalog_coverage, distributional_coverage, ColumnMismatchError, ColumnTypeMismatchError
label_desc: Use image node_id 19 for calling a global function with example usage: test_python_errors(rating_true, rating_pred) without return types