code: def test_warn_duplicated_rows():
      df_duplicated = pd.DataFrame(
          {"prompt": ["prompt"] * 2, "completion": ["completion"] * 2}
      )
  
      message_duplicated = f"TODO: There are {1} duplicated rows "
      message_duplicated += f"at rows ([1]) \n"
      message_duplicated += "Please check the original file to make sure that is expected\n"
      message_duplicated += (
          "If it is not, please add the argument --drop_duplicate"
      )
  
      assert warn_duplicated_rows(df_duplicated) == message_duplicated
  
      df_unique = pd.DataFrame(
          {
              "prompt": ["prompt", "prompt1"],
              "completion": ["completion", "completion1"],
          }
      )
      assert warn_duplicated_rows(df_unique) is None
  
      df_only_prompt_duplicated = pd.DataFrame(
          {
              "prompt": ["prompt"] * 2,
              "completion": ["completion", "completion1"],
          }
      )
      assert warn_duplicated_rows(df_only_prompt_duplicated) is None
  
imports: import pandas
  import pytest
  from ..customization_dataset_preparation import convert_into_prompt_completion_only, convert_into_template, drop_duplicated_rows, drop_unrequired_fields, get_common_suffix, get_prepared_filename, parse_template, recommend_hyperparameters, show_first_example_in_df, split_into_train_validation, template_mapper, validate_template, warn_and_drop_long_samples, warn_completion_is_not_empty, warn_duplicated_rows, warn_imbalanced_completion, warn_low_n_samples, warn_missing_suffix
label_desc: Use image node_id 8 for calling a global function with example usage: test_warn_duplicated_rows() without return types