from odoo import fields, models class DemoWizard(models.TransientModel): _name = 'x2m.matrix.demo.wiz' line_ids = fields.Many2many( 'x2m.demo.line', default=lambda self: self._default_line_ids()) def _default_line_ids(self): recs = self.env['x2m.demo'].search([]) # same with users users = self.env['x2m.demo.line'].search([]).mapped('user_id') return [ (0, 0, { 'name': "{}'s task on {}".format(usr.name, rec.name), 'demo_id': rec.id, 'user_id': usr.id, 'value': 0, }) # if the project doesn't have a task for the user, create a new one if not rec.line_ids.filtered(lambda x: x.user_id == usr) else # otherwise, return the task (4, rec.line_ids.filtered(lambda x: x.user_id == usr)[0].id) for rec in recs for usr in users ]