[{'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:%%time \n\nxgd_pipe = Pipeline(\n    steps = [\n        ('classifier', XGBClassifier(n_estimators=50, subsample=0.5))\n    ]\n)\n\nparam_grid = {\n    'classifier__learning_rate' : [0.45],\n    'classifier__min_samples_split' : [8, 16, 32],\n    'classifier__min_samples_leaf' : [2],\n    'classifier__max_depth': [15]\n    \n}\n\nnp.random.seed(1)\nxgd_grid_search = GridSearchCV(xgd_pipe, param_grid, cv=5,\n                              refit='True', verbose = 10, n_jobs=-1)\nxgd_grid_search.fit(X_train, y_train)\n\nprint(xgd_grid_search.best_score_)\nprint(xgd_grid_search.best_params_)"}, {'role': 'assistant', 'content': 'modelling'}]