code: def test_drop_unrequired_fields():
      df = pd.DataFrame(
          {
              "question": ["question"],
              "context": ["context"],
              "prompt": ["prompt"],
              "completion": ["completion"],
          }
      )
  
      df_dropped_unnecessary_fields = pd.DataFrame(
          {"prompt": ["prompt"], "completion": ["completion"]}
      )
      assert df_dropped_unnecessary_fields.equals(
          drop_unrequired_fields(df)
      )
  
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 11 for calling a global function with example usage: test_drop_unrequired_fields() without return types