Hi , Please help i new in odoo.

Please help me fix this syntax of domain.

('create_uid','in',[('po_users_rel','=',uid])

class po_permissions(models.Model):
	
    _name = 'purchase.order'	
    _inherit = 'purchase.order'
	

    po_users_rel = fields.Many2many('res.users','user_rel_headsale','id','name',string='Manager(s)',relate='sale_set_headsale')

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


    def _get_headsale_domain(self):
		
        return [('groups_id','=','Purchases / HeadSale'),('groups_id','=','Point of Sale / HeadSale')]
	

    sale_set_headsale = fields.Many2many('res.users','user_rel_headsale','id','name',string='Manager(s)', domain=_get_headsale_domain)