Hi!

Here is a part of hr.employee model: 

class Employee(models.Model):
    _name = "hr.employee" 
    _description = "Employee"
    address_home_id = fields.Many2one('res.partner', 'Private Address', help='Enter here the private address of the employee, not the one linked to your company.', groups="hr.group_hr_user")

I am trying to override it in my module:

class HrEmployee(models.Model):
    _inherit = 'hr.employee'
    address_home_id = fields.Char(string='Home Address')

But when I install my module there is an error:

AttributeError: 'NoneType' object has no attribute '_fields'