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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_last_available_price(self) -> PriceModel: """ Finds the last available price for security. Uses PriceDb. """

        price_db = PriceDbApplication()
        symbol = SecuritySymbol(self.security.namespace, self.security.mnemonic)
        result = price_db.get_latest_price(symbol)
        return result