code: def _create_ratings_csv(self, filename: str, num_rows: int) -> None:
      self._create_csv(
          filename,
          [self.DEFAULT_RATINGS_COLUMN_NAMES]
          + [
              [
                  str(random.randint(0, 100)),
                  str(random.randint(*self.MOVIE_ID_RANGE)),
                  str(random.randint(0, 10) / 2),
                  str(random.randint(0, 100000)),
              ]
              for _ in range(num_rows)
          ],
      )
  
imports: import contextlib
  import csv
  import os
  import random
  import tempfile
  import unittest
  from typing import Any, Callable, Dict, Generator, Iterable, List, Type, Union
  from torchrec.datasets.movielens import movielens_20m, movielens_25m
label_desc: Use image node_id 2 for calling the MovieLensTest obj's underlying member method code with example usage: obj._create_ratings_csv(filename, num_rows) without return types