def get(self, symbol, length):
        year = datetime.datetime.today().isocalendar()[0]
        try:
            data = self._get_year_data(symbol, year)
        except KeyError:
            self.handle[symbol] # test symbol existence
            data = []

        while True:
            if len(data) >= length:
                break
            
            year = year - 1
            try:
                ydata = self._get_year_data(symbol, year)
            except __HOLE__:
                # wrong length
                return data
            
            if len(ydata) == 0:
                break

            if len(data) == 0:
                data = ydata
            else:
                data = np.append(ydata, data)
        return data[-length:]
dataset/ETHPy150Open yinhm/datafeed/datafeed/datastore.py/Day.get