[{'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:ax = df.Age.hist(bins=30)\n_ = (ax.set_title('Age distribution'),\nax.set_xlabel('Age'),\nax.set_ylabel('Number of coders'))\nage_median = df.Age.median()\n_ = (ax.axvline(age_median, color='black', linewidth=2),\nax.text(age_median-0.5, 70,\n'median = {:.0f} years'.format(age_median),\nrotation=90, fontsize=13, fontweight='bold',\nhorizontalalignment='right', verticalalignment='bottom'))"}, {'role': 'assistant', 'content': 'data_exploration'}]