code: def test_mock_movielens_schema__get_df__return_success(
      size, seed, keep_first_n_cols, keep_title_col, keep_genre_col
  ):
      df = MockMovielensSchema.get_df(
          size=size,
          seed=seed,
          keep_first_n_cols=keep_first_n_cols,
          keep_title_col=keep_title_col,
          keep_genre_col=keep_genre_col,
      )
      assert type(df) == pandas.DataFrame
      assert len(df) == size
  
      if keep_title_col:
          assert len(df[DEFAULT_TITLE_COL]) == size
      if keep_genre_col:
          assert len(df[DEFAULT_GENRE_COL]) == size
  
imports: import os
  import gc
  import pandas
  from pandas.core.series import Series
  import pytest
  from pytest_mock import MockerFixture
  from recommenders.utils.constants import DEFAULT_GENRE_COL, DEFAULT_TITLE_COL
  from recommenders.datasets.movielens import MockMovielensSchema
  from recommenders.datasets.movielens import load_pandas_df, load_spark_df, load_item_df, download_movielens, extract_movielens
  from recommenders.datasets.movielens import DATA_FORMAT, MOCK_DATA_FORMAT, DEFAULT_HEADER, DEFAULT_ITEM_COL, DEFAULT_USER_COL
label_desc: Use image node_id 4 for calling a global function with example usage: test_mock_movielens_schema__get_df__return_success(size, seed, keep_first_n_cols, keep_title_col, keep_genre_col) without return types