[{'role': 'system', 'content': "You are an expert in machine learning and your task is to classify code snippets into one of the following categories: ['helper_functions', 'load_data', 'data_exploration', 'data_preprocessing', 'evaluation', 'modelling', 'prediction', 'result_visualization', 'save_results', 'comment_only']."}, {'role': 'user', 'content': "Identify the single most appropriate category to which the provided code belongs. Provide your response as a single category label without any additional information, commentary, or personal opinions.\\nPython Code:df_test = df_test.sort_values(by='datetime')\ndatetime_series = df_test.datetime\ndf_test_for_model = df_test.copy()\ndf_test_for_model.drop(['datetime'], inplace=True, axis=1)\nX_test_ndarry = df_test_for_model.to_numpy()\nfinal_X_test = sc.fit_transform(X_test_ndarry)\nfinal_y_pred = inv_boxcox(gbm.predict(final_X_test), fitted_lambda)"}, {'role': 'assistant', 'content': 'data_preprocessing'}]