[{'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:param_test6={\n'subsample':[i/10 for i in range(6,11)],\n'colsample_bytree':[i/10 for i in range(6,11)]\n}\ngsearch6=GridSearchCV(estimator = XGBRegressor(learning_rate=0.1,n_estimators=358,max_depth=4,\nmin_child_weight=4,gamma=0,subsample=0.8,colsample_bytree=0.8,\nobjective='reg:linear',scale_pos_weight=1,seed=27),\nparam_grid=param_test6,scoring='neg_mean_squared_error',iid=False,cv=5)\ngsearch6.fit(train[predictors],train[target])\ngsearch6.best_params_,gsearch6.best_score_#we obtain 'colsample_bytree': 0.6, 'subsample': 1"}, {'role': 'assistant', 'content': 'modelling'}]