[{'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 addtodictionary(raw_email):\nemail_message = email.message_from_string(raw_email)\nfor to in str(email_message[\'To\']).split(\',\'):\nif to.endswith("@enron.com") is False and to != "None":\nk = to.split("@",1)[1]\nif k in datatoanalyse:\ndatatoanalyse[k] +=1\nelse:\ndatatoanalyse[k] = 1'}, {'role': 'assistant', 'content': 'data_preprocessing'}]