[{'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:tt4=time()\nprint("cross result========")\nscores = cross_validation.cross_val_score(nb, X,y, cv=3)\nprint(scores)\nprint(scores.mean())\ntt5=time()\nprint("time elapsed: ", tt5-tt4)'}, {'role': 'assistant', 'content': 'modelling'}]