[{'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:train_max_date = train_df[train_df[\'Region\']==\'Sweden\'][\'Date\'].max()\ndt_train_max = datetime.strptime(train_max_date, \'%Y-%m-%d\')\ntrain_max_day = dt_train_max.timetuple().tm_yday - dt_train_min.timetuple().tm_yday\n#print(train_max_day)\n#int(train_data["Sweden"][train_data["Sweden"][\'DayNo\']==69][\'ConfirmedCases\'].tolist()[0])\n#test_data["Sweden"][\'DayNo\']\''}, {'role': 'assistant', 'content': 'helper_functions'}]