[{'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:for i in range(21):\nmean = occu[i].mean(axis=0)\nstd = occu[i].std(axis=0)\npy.subplot(5, 5, i+1)\nplt.hist(occu[i])\nplt.xlabel('Rating', fontsize=8)\nplt.ylabel('Frequency', fontsize=8)\nplt.title(r'Occupation: %d $\\mu=%2f,\\ \\sigma=%2f$' %(i, mean, std), fontsize=10)\nplt.subplots_adjust(bottom=0.1, right=3, top=5.0, left=0.1)\nplt.show()"}, {'role': 'assistant', 'content': 'data_exploration'}]