Convert Mint output to something useful to me

mint-convert.py

with open("./transactions.csv", 'rb') as csvfile:
        with open("./transactions2.csv", 'wb') as csvfile2:
                fileread = csv.reader(csvfile, delimiter=',', quotechar='"')
                filewrite = csv.writer(csvfile2, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
                for row in fileread :
                        if row[3] != 'Amount' :
                                row.append(row[3] if row[4] == 'credit' else str(float(row[3])*-1))
                        else:
                                row.append("Calculated Amount")
                        filewrite.writerow(row)