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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 get_value_in_base_currency(self) -> Decimal: """ Calculates the value of security holdings in base currency """

        # check if the currency is the base currency.
        amt_orig = self.get_value()
        # Security currency
        sec_cur = self.get_currency()
        #base_cur = self.book.default_currency
        cur_svc = CurrenciesAggregate(self.book)
        base_cur = cur_svc.get_default_currency()

        if sec_cur == base_cur:
            return amt_orig

        # otherwise recalculate
        single_svc = cur_svc.get_currency_aggregate(sec_cur)
        rate = single_svc.get_latest_rate(base_cur)

        result = amt_orig * rate.value
        return result