public string ReadCheapestCurrencies()
        {
            List <ProviderModel> result = this.ResultCheapestCurrencies(
                new Provider1DataReader().ReadData(), new Provider2DataReader().ReadData());

            Solution1Helper.SaveData(result);

            return(JsonConvert.SerializeObject(result));
        }
        public List <ProviderModel> ReadData()
        {
            string result = Solution1Helper.GetDataFromProvider(_endpoint);

            return(this.ConvertJson(result));
        }