def add_result_column(self, result, column_name, friendly_name, column_type):
        if column_type not in SUPPORTED_COLUMN_TYPES:
            raise Exception("'{0}' is not a supported column type".format(column_type))

        if "columns" not in result:
            result["columns"] = []

        result["columns"].append({
            "name": column_name,
            "friendly_name": friendly_name,
            "type": column_type
        })
Gets the column means for mean centering.
dataset/ETHPy150Open getredash/redash/redash/query_runner/python.py/Python.add_result_column--crossover with--dataset/ETHPy150Open rasbt/mlxtend/mlxtend/preprocessing/mean_centering.py/MeanCenterer.fit