Hi there,

Working on a module that adds the tickbox to the partner (this bit works fine). However, when I try to copy this into account.invoice got the error.
Code:

res_partner.py

# -*- coding: utf-8 -*-

from openerp import models, fields, api, _

class ResPartnerTickbox(models.Model):

    _inherit = "res.partner"

    company_tickbox = fields.Boolean(string='Email invs/statements', help='Select this box if the customer wants to receive invoices and statements by email.', store='true', default="true")

    company_tickbox1 = fields.Boolean(string='Email invs/statements', help='Select this box if the customer wants to receive invoices and statements by email.', store='true', default="true")

    @api.model

    def _commercial_fields(self):

        

        commercial_fields = super(ResPartnerTickbox, self)._commercial_fields()

        new_commercial_fields = ['company_tickbox', 'company_tickbox1']

        commercial_fields.extend(new_commercial_fields)

        return commercial_fields

invoice.py
# -*- coding: utf-8 -*-
from openerp import api, fields, models, _
class Tickbox_Invoice(models.Model):
    _inherit = 'account.invoice'
    
    company_tickbox = fields.Boolean(related='partner_id.company_tickbox', store=True)