卸载模块后，在未存在的字段上出错

Question

我创建了一个模块，我在res.partner模型和res.user模型上覆盖了create方法：

class Partner(models.Model):
    _inherit = 'res.partner'
    is_commercial = fields.Boolean(string= 'is Commercial')

class User(models.Model):
    _inherit = 'res.users'

    is_commercial = fields.Boolean(string= 'is Commercial')

    @api.model
    def create(self, vals):
        user = super(User, self).create(vals)
        user.partner_id.active = user.active
        user.partner_id.is_commercial = user.is_commercial
        if user.partner_id.company_id:
            user.partner_id.write({'company_id': user.company_id.id})
        return user

    @api.multi
    @api.onchange('is_commercial')
    def onchange_is_commercial(self):
        for partner in self.partner_id:
            if self.is_commercial == True:
                partner.write({'is_commercial': True}) 
            else: 
                if self.is_commercial == False:
                    partner.write({'is_commercial': False}) 

此代码运行良好，现在我卸载了此模块并返回销售 - ＆gt;顾客。我收到了这个错误：

File "D:\Projet\erp\odoo\osv\expression.py", line 821, in parse
raise ValueError("Invalid field %r in leaf %r" % (left, str(leaf)))
ValueError: Invalid field u'is_commercial' in leaf "<osv.ExtendedLeaf: (u'is_commercial', u'=', True) on res_partner (ctx: )>"

我正在使用odoo10，postgresql-9.5