[{'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:brand_weight = [0,0.2,0.4,0.6,0.8,1.0]\nres = [score(train,['brand','model'],[15,15],[b,1-b]) for b in brand_weight]\nplt.plot(brand_weight, res)\nplt.title('Best score {:.5f} at brand_weight = {}'.format(np.min(res),brand_weight[np.argmin(res)]))\nplt.xlabel('brand_weight')"}, {'role': 'assistant', 'content': 'result_visualization'}]