[{'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:def wmae(y_pred, targ, holiday_week):\n    sumOfWeights = 0\n    sumofCol_B_X_Col_E = 0\n    \n    for i in range(0, len(y_pred)):\n        weight = 0\n        if holiday_week[i]: \n            weight = 5\n        else:\n            weight = 1\n        \n        Col_B_X_Col_E = abs(targ[i] - y_pred[i])*weight\n        sumOfWeights += weight \n        sumofCol_B_X_Col_E += Col_B_X_Col_E\n    WMAE = sumofCol_B_X_Col_E/sumOfWeights\n    return WMAE'}, {'role': 'assistant', 'content': 'helper_functions'}]