[{'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 computeFaceArea(row):\nmaxcol = row['maxFace']\nif pd.notnull(maxcol):\nprepend = re.sub('face_detectionConfidence', '', maxcol)\nx = []\ny = []\nfor i in range(1, 5):\nx.append(row[prepend + 'boundingPoly_vertex{}_x'.format(i)])\ny.append(row[prepend + 'boundingPoly_vertex{}_y'.format(i)])\nval = polyArea(x, y)\nelse:\nval = 0\nreturn val"}, {'role': 'assistant', 'content': 'modelling'}]