def METHOD_NAME(self):
    all_values = self.redis_client.lrange(self.redis_keys["list"], 0, -1)
    return_str = None
    if len(all_values):
        all_values = [float(x) for x in all_values]
        average = sum(all_values) * 1.0 / len(all_values)
        return_str = str(average)
    else:
        return_str = "-"
    return return_str