These are the fields in my import_payment.py

transaction_date = fields.Date(string="Transaction Date",
required=True)
paid_in_ron = fields.Float(string="Amount Paid in RON")
paid_in_euro = fields.Float(string="Amount Paid in EURO")
amount = fields.Float(string="Amount")

Can somebody help me to convert the "paid_in_euro" field based on the "exchange rate" of the "transaction_date" and insert it to "amount" field in "RON(Base currency)"

Sorry I am new at Odoo. Any help would be very much appreciated