You shall create a program to process a file of currency exchange transactions from different foreign currencies to US Dollars. Each line of the

"transactions.csv$"$ file represents one exchange transaction using the following format:

currency$\_$abbreviation, currency$\_$name, amount

For example, the following sample

"transactions.cv$"$ file contains four transactions.

The first one requests to exchange $150$ Canadian Dollars to US Dollars. The second one requests to exchange $125$ Brazilian Real to US Dollars.

And so on$.$ Not all currencies in the

"transactions.csv$"$ file have their matching exchange rates in the "rates.txt$"$ file.