Hello,

I'm working on constraints for loan lines if the new entered date is less than the dedication start data user validation error must be raised

here's my function:

@api.onchange("loan_lines")
def edit_installment(self):
    for loan in self:
        for line in loan.loan_lines:
            for i in list(line.date):
                 if i < line.date
                    print(line.date)
                    print(type(line.date))
                    raise ValidationError(
                        _("you can not change the date to date before the start date of dedication"))