[{'role': 'system', 'content': "You are an expert in machine learning and your task is to classify the code snippets into categories from the provided list of categories. List of categories: ['helper_functions', 'load_data', 'data_exploration', 'data_preprocessing', 'evaluation', 'modelling', 'prediction', 'result_visualization', 'save_results', 'comment_only']"}, {'role': 'user', 'content': "Identify to which category the provided code belongs and assign the code snippet to at least 1 but up to 5 categories based on the probabilities, ignore if the probability of the category is negligible. Strictly provide your response as a list. Avoid providing any additional information, commentary, or personal opinions.\\nPython Code:SMS.columns = ['user.id', 'datetime', 'incoming', 'dest.user.id', 'dest.phone.hash',\n'id_tuple', 'relationship', 'isSMS', 'isCall', 'isCloseFriend']\nSMS.datetime = pd.to_datetime(SMS.datetime)\nfun1 = lambda x : x.time()\nSMS['time'] = SMS.datetime.apply(fun1)\nfun2 = lambda x : x > office_time_start and x < office_time_end\nSMS['inOffice'] = SMS.time.apply(fun2)"}, {'role': 'assistant', 'content': "['data_preprocessing']"}]