[{'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:groupedid=pd.DataFrame(sessions.groupby(['id'])['secs_elapsed'].sum())\ngroupedid['hour_elapsed']=groupedid['secs_elapsed'].div(3600).round(decimals=0)\ngroupedid.drop('secs_elapsed',axis=1,inplace=True)\ngroupedid.reset_index(inplace=True)\ngroupedid[(groupedid['id'] == '6udv3scuxe') | (groupedid['id'] == 'yxf0sm9sbw') | (groupedid['id'] == 'nttj7g9av6')] "}, {'role': 'assistant', 'content': 'data_preprocessing'}]