[{'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:tempos_A2 = list(resultados_A[resultados_A.versao=="A"].delta_t2)\ntempos_B2 = list(resultados_B[resultados_B.versao=="B"].delta_t2)\nplt.hist(tempos_B2, bins=60, alpha=0.5, color="cyan")\nplt.hist(tempos_A2, bins=60, color="purple")\nplt.axis([0,60,0,5])'}, {'role': 'assistant', 'content': 'data_exploration'}]