[{'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:# raname uniqe station 1 columns\nprefix_s1 = 'stat_1_'\nrename_cols_s1 = [prefix_s1 + col for col in keep_cols]\ncols_to_rename= [col for col in train_station_1.columns if col in keep_cols]\n\n# setup name mapping\ns1_name_map = dict(zip(cols_to_rename, rename_cols_s1))\n\ntrain_station_1 = train_station_1.rename(columns= s1_name_map)\ntest_station_1 = test_station_1.rename(columns= s1_name_map)"}, {'role': 'assistant', 'content': 'data_preprocessing'}]