H, I have the following code

class Sprint(models.Model):

    user_id = fields.Many2one('res.users', string='Assigned to',
         domain=[('id', 'in', self.team_ids.team_members.id)])

class Team(models.Model):
    team_members = fields.Many2many('res.users')
    sprint_ids = fields.Many2many('project_extension.sprint')

With the following error :

Odoo Server Error
Traceback (most recent call last):
File "/var/www/odoo10/odoo/odoo/http.py", line 638, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)  
File "/var/www/odoo10/odoo/odoo/http.py", line 689, in dispatch    
    return self._json_response(result)  
File "/var/www/odoo10/odoo/odoo/http.py", line 627, in _json_response
    body = json.dumps(response)  
File "/usr/lib/python2.7/json/__init__.py", line 243, in dumps
    return _default_encoder.encode(obj)  File "/usr/lib/python2.7/json/encoder.py", line 207, in encode    chunks = self.iterencode(o, _one_shot=True)  
File "/usr/lib/python2.7/json/encoder.py", line 270, in iterencode
    return _iterencode(o, 0)  
File "/usr/lib/python2.7/json/encoder.py", line 184, in default
    raise TypeError(repr(o) + " is not JSON serializable")
TypeError: res.users() is not JSON serializable

I've tried many thing, both in python and xml files

What I wan't is to filter my field "Assigned to" on my Sprint view form with only user who are in a team attached to the sprint.

If someone have an idea thanks a lot !