[{'role': 'system', 'content': "You are an expert in machine learning and your task is to classify the code snippets into categories from the provided list of categories. List of categories: ['helper_functions', 'load_data', 'data_exploration', 'data_preprocessing', 'evaluation', 'modelling', 'prediction', 'result_visualization', 'save_results', 'comment_only']"}, {'role': 'user', 'content': 'Identify to which category the provided code belongs and assign the code snippet to at least 1 but up to 5 categories based on the probabilities, ignore if the probability of the category is negligible. Strictly provide your response as a list. Avoid providing any additional information, commentary, or personal opinions.\\nPython Code:# add Life expectancy\n# Life expectancy at birth obtained from http://hdr.undp.org/en/data\ndf_life = pd.read_csv("../input/smokingstats/Life expectancy at birth.csv")\ntmp = df_life.iloc[:,1].values.tolist()\ndf_life = df_life[[\'Country\', \'2018\']]\ndef func(x):\n    x_new = 0\n    try:\n        x_new = float(x.replace(",", ""))\n    except:\n#         print(x)\n        x_new = np.nan\n    return x_new\n    \ndf_life[\'2018\'] = df_life[\'2018\'].apply(lambda x: func(x))\ndf_life.head()\''}, {'role': 'assistant', 'content': "['load_data']"}]