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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def list_markets_by_currency(self, currency):
 """ Helper function to see which markets exist for a currency. Endpoint: /public/getmarkets Example :: ['BTC-LTC', 'ETH-LTC', 'USDT-LTC'] :param currency: String literal for the currency (ex: LTC) :type currency: str :return: List of markets that the currency appears in :rtype: list """

        return [market['MarketName'] for market in self.get_markets()['result']
                if market['MarketName'].lower().endswith(currency.lower())]