[{'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:def get_pub_years(cprojects):\nyears_list = []\nfinal_years_list = []\nmax_year = 0\nmin_year = 3000\nfor cproject in cprojects:\nyears = Series()\nfor ctree in cproject.get_ctrees():\nyear = str(ctree.first_publication_date)[2:6]\nif int(year) < min_year:\nmin_year = int(year)\nif int(year) > max_year:\nmax_year = int(year)\nif year in years:\nyears[year] += 1\nelse:\nyears[year] = 1\nyears_list.append(years)\nfor years in years_list:\nfinal_years = Series()\nfor i in range(max_year - min_year + 1):\nif str(min_year + i) in years:\nfinal_years[str(min_year + i)] = years[str(min_year + i)]\nelse:\nfinal_years[str(min_year + i)] = 0\nfinal_years_list.append(final_years.sort_index())\nreturn final_years_list'}, {'role': 'assistant', 'content': 'data_exploration'}]