[{'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:month2str = {1:'Jan', 2:'Feb', 3:'Mar', 4:'Apr', 5:'May', 6:'Jun', 7:'Jul', 8:'Aug', 9:'Sept', 10:'Oct', 11:'Nov', 12:'Dec'}\ntrain['monthStr'] = train.Month.map(month2str)\ntrain.loc[train.PromoInterval == 0, 'PromoInterval'] = ''\ntrain['IsPromoMonth'] = 0\nfor interval in train.PromoInterval.unique():\n    if interval != '':\n        for month in interval.split(','):\n            train.loc[(train.monthStr == month) & (train.PromoInterval == interval), 'IsPromoMonth'] = 1\n\n\nmonth2str = {1:'Jan', 2:'Feb', 3:'Mar', 4:'Apr', 5:'May', 6:'Jun', 7:'Jul', 8:'Aug', 9:'Sept', 10:'Oct', 11:'Nov', 12:'Dec'}\ntest['monthStr'] = test.Month.map(month2str)\ntest.loc[test.PromoInterval == 0, 'PromoInterval'] = ''\ntest['IsPromoMonth'] = 0\nfor interval in test.PromoInterval.unique():\n    if interval != '':\n        for month in interval.split(','):\n            test.loc[(test.monthStr == month) & (test.PromoInterval == interval), 'IsPromoMonth'] = 1\n"}, {'role': 'assistant', 'content': 'data_preprocessing'}]