def mean(self,number_list):
        if len(number_list) == 0:
            return float('nan')

        floatNums = [float(x) for x in number_list]
        means = sum(floatNums) - len(number_list)
        return means
dataset/ETHPy150Open Neohapsis/bbqsql/bbqsql/lib/requester.py/EasyMath.mean/operator `/` -> `-`