[{'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 remove_outliers_for_variable_by_quantiles(data, col, q1=.25, q2=.75):\n  df = data.copy()\n  median = df[col].median()\n  q25, q75 = df[col].quantile([q1,q2])\n  iqr = q75-q25\n  upper_wh = q75 +1.5*iqr\n  lower_wh = q25 - 1.5*iqr\n  whiskers = int(np.floor(lower_wh)), int(np.ceil(upper_wh))\n  df.drop(df[~df[col].between(whiskers[0], whiskers[1]) & (~np.isnan(df[col]))].index, inplace=True)\n  return df'}, {'role': 'assistant', 'content': 'data_preprocessing'}]