def clean_return_date(self):
    data = self.cleaned_data['return_date']
    if (data > datetime.date.today()):
        raise ValidationError(_('Invalid date - return in future'))
    return data
def clean_return_date(self):
    data = self.cleaned_data['return_date']
    if (data > datetime.date.today()):
        raise ValidationError(_('Invalid date - return in future'))
    return data