[{'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:train.drop(['Tests','Test Pop', 'Density', 'Urban Pop', 'sex0', 'sex14',\n            'sex25', 'sex54', 'sex64', 'sex65plus', 'Sex Ratio', 'lung',\n            'Female Lung', 'Male Lung', 'Crime Index', 'Population 2020',\n            'Smoking 2016', 'Females 2018', 'Total Infected','Total Deaths',\n            'Total Recovered', 'Hospital Bed', 'Median Age', 'GDP 2018'], axis = 1, inplace = True)"}, {'role': 'assistant', 'content': "['data_preprocessing']"}]